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Fatoni, Ahmad, Mauizatul Hasanah, Lasmaryna Sirumapea, Annisa Defanie Putri, Khoirunnisa Sari, Restu Dwi Khairani e Nurlisa Hidayati. "Synthesis, Characterization of Polyvinyl Alcohol-Chitosan-ZnO/CuO Nanoparticles Film and Its Biological Evaluation as An Antibacterial Agent of Staphylococcus aureus". al-Kimiya 10, n.º 1 (30 de junho de 2023): 1–12. http://dx.doi.org/10.15575/ak.v10i1.24725.
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The polyvinyl alcohol-chitosan-ZnO/CuO nanoparticles film was researched. Synthesis, characterization, and its biological evaluation as an antibacterial of Staphylococcus aureus were the aims of this research. The biosynthesis of ZnO, CuO, and ZnO/CuO nanoparticles was done using the biological method. The polyvinyl alcohol-chitosan-ZnO/CuO nanoparticles film was synthesized using the casting method. All the products were characterized by FTIR spectroscopy, X-ray diffraction, and Scanning Electron Microscope (SEM). Polyvinyl alcohol-chitosan-ZnO/CuO nanoparticles film as a paper disk for the evaluation as an antibacterial agent through the agar disk diffusion method. The absorption bands of ZnO, CuO, and ZnO/CuO nanoparticles can be observed at 318, 274, and 252 nm, respectively. The peaks at wavenumbers 433-673 and 619 cm-1 were Zn-O and Cu-O groups, respectively. The Zn-O and Cu-O groups at ZnO/CuO nanoparticles can be observed at 474 and 619 cm-1. The appearance of Zn-O and Cu-O groups at film PVA-chitosan-ZnO/CuO nanoparticles indicates the wavenumber between 433 and 673 cm-1. The physical structure of ZnO, CuO, and ZnO/CuO nanoparticles is crystalline form. The crystallite size of ZnO, CuO, and ZnO/CuO nanoparticles was estimated at 1.0572, 6.6315, and 2.3333 nm respectively. The physical structure of film PVA-chitosan-ZnO/CuO nanoparticles is amorphous. The surface morphology of films C, D, and E was affected by the addition of chitosan and ZnO/CuO nanoparticles. The film of PVA-chitosan-ZnO/CuO nanoparticles (C, D and E) can act as an antibaterial agent of Staphylococcus aureus.The inhibition zone of film D is higher than A, B, C, and E.
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Fatoni, Ahmad, Agnes Rendowati, Lasmaryna Sirumapea, Lidya Miranti, Siti Masitoh e Nurlisa Hidayati. "Synthesis, Characterization of Chitosan-ZnO/CuO Nanoparticles Film, and its Effect as an Antibacterial Agent of Escherichia coli". Science and Technology Indonesia 8, n.º 3 (6 de julho de 2023): 373–81. http://dx.doi.org/10.26554/sti.2023.8.3.373-381.
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The film of chitosan- ZnO/CuO nanoparticles was synthesized. This study were the synthesis and characterization of the chitosan-ZnO/CuO nanoparticles film and its effect as an antibacterial of Escherichia coli. The ZnO, CuO, and ZnO/CuO were biosynthesized by biological method and for the synthesis of the chitosan-ZnO/CuO nanoparticles film, the casting method was adopted. The product was analyzed by FTIR spectroscopy, X-ray diffraction (XRD), and Scanning Electron Microscope (SEM), respectively. The product of chitosan-ZnO/CuO nanoparticles film as paper disk and agar disk diffusion method was selected to study an antibacterial agent of this product. The Zn-O or Cu-O group was observed at a peak between 468-675 cm−1 for ZnO and 503 and 619 cm−1 for CuO nanoparticles, respectively. ZnO, CuO, and ZnO/CuO nanoparticles are in the crystalline form and it has a crystallite size of 13.21, 13.21, and 11.49 nm respectively. After interacting with chitosan, the metal nanoparticles such as ZnO, CuO, and ZnO/CuO nanoparticles can change the crystalline form of chitosan to be amorphous form. The addition of ZnO, CuO, and ZnO/CuO nanoparticles in the chitosan will change the surface morphology of chitosan. Chitosan-ZnO/CuO nanoparticles film can inhibit the growth of Escherichia coli bacteria.
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Fadlly, Teuku Andi, e Rachmad Almi Putra. "CURRENT-VOLTAGE CHARACTERISTICS OF SOLAR CELLS p-n JUNCTION ZnO AND TiO2 PARAREL ON Cu2O LAYER". Jurnal Neutrino 12, n.º 1 (30 de janeiro de 2020): 1. http://dx.doi.org/10.18860/neu.v12i1.7578.
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Current-Voltage Characteristics of solar cells p-n junction ZnO and TiO<sub>2</sub> parallel in the Cu<sub>2</sub>O layer has been determined using solar irradiation. Metal oxide has been used as a semiconductor material, such as ZnO and TiO<sub>2</sub> is an n-type semiconductor. The material has a gap energy of 3.37 eV and 3.2 eV. Thermal oxidation is applied to commercial Cu plates for 60 minutes to produce Cu<sub>2</sub>O layers as p-type semiconductors. The process varies in temperature, namely 300, 400, and 500 °C. The process of thermal oxidation on Cu plates at a temperature of 300 °C increases the impurity in the Cu<sub>2</sub>O layer. The impurity layer is CuO. Then the CuO layer formed decreases with increasing temperature thermal oxidation. CuO layer increases the efficiency of solar cells p-n junction TiO<sub>2</sub>-ZnO parallel in the layer Cu<sub>2</sub>O. The results of measurements with sunlight showed that the TiO<sub>2</sub>-ZnO/Cu<sub>2</sub>O (300) samples had the highest solar cell efficiency, which was 0.28 %.
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Zou, Xinwei, Huiqing Fan, Yuming Tian, Mingang Zhang e Xiaoyan Yan. "Chemical bath deposition of Cu2O quantum dots onto ZnO nanorod arrays for application in photovoltaic devices". RSC Advances 5, n.º 30 (2015): 23401–9. http://dx.doi.org/10.1039/c4ra13776k.
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A protective CuO layer on the Cu2O quantum dots was prepared by simply heat-treating the Cu2O/ZnO hetero-nanorod arrays in ambient air, which enhances the photovoltaic stability.
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Chan, Yu Bin, Mohammod Aminuzzaman, Lai-Hock Tey, Yip Foo Win, Akira Watanabe, Sinouvassane Djearamame e Md Akhtaruzzaman. "Impact of Diverse Parameters on the Physicochemical Characteristics of Green-Synthesized Zinc Oxide–Copper Oxide Nanocomposites Derived from an Aqueous Extract of Garcinia mangostana L. Leaf". Materials 16, n.º 15 (2 de agosto de 2023): 5421. http://dx.doi.org/10.3390/ma16155421.
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Compared to conventional metal oxide nanoparticles, metal oxide nanocomposites have demonstrated significantly enhanced efficiency in various applications. In this study, we aimed to synthesize zinc oxide–copper oxide nanocomposites (ZnO-CuO NCs) using a green synthesis approach. The synthesis involved mixing 4 g of Zn(NO3)2·6H2O with different concentrations of mangosteen (G. mangostana) leaf extract (0.02, 0.03, 0.04 and 0.05 g/mL) and 2 or 4 g of Cu(NO3)2·3H2O, followed by calcination at temperatures of 300, 400 and 500 °C. The synthesized ZnO-CuO NCs were characterized using various techniques, including a UV-Visible spectrometer (UV-Vis), photoluminescence (PL) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD) analysis and Field Emission Scanning Electron Microscope (FE-SEM) with an Energy Dispersive X-ray (EDX) analyzer. Based on the results of this study, the optical, structural and morphological properties of ZnO-CuO NCs were found to be influenced by the concentration of the mangosteen leaf extract, the calcination temperature and the amount of Cu(NO3)2·3H2O used. Among the tested conditions, ZnO-CuO NCs derived from 0.05 g/mL of mangosteen leaf extract, 4 g of Zn(NO3)2·6H2O and 2 g of Cu(NO3)2·3H2O, calcinated at 500 °C exhibited the following characteristics: the lowest energy bandgap (2.57 eV), well-defined Zn-O and Cu-O bands, the smallest particle size of 39.10 nm with highest surface area-to-volume ratio and crystalline size of 18.17 nm. In conclusion, we successfully synthesized ZnO-CuO NCs using a green synthesis approach with mangosteen leaf extract. The properties of the nanocomposites were significantly influenced by the concentration of the plant extract, the calcination temperature and the amount of precursor used. These findings provide valuable insights for researchers seeking innovative methods for the production and utilization of nanocomposite materials.
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Sakib, Abdullah Al Mamun, Shah Md Masum, Jan Hoinkis, Rafiqul Islam e Md Ashraful Islam Molla. "Synthesis of CuO/ZnO Nanocomposites and Their Application in Photodegradation of Toxic Textile Dye". Journal of Composites Science 3, n.º 3 (17 de setembro de 2019): 91. http://dx.doi.org/10.3390/jcs3030091.
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CuO/ZnO composites are synthesized using a simple mechanochemical combustion method. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier transform infrared (FTIR) are used to characterize the prepared oxides. X-ray diffraction reveals that the prepared CuO/ZnO exhibit a wurtzite ZnO crystal structure and the composites are composed of CuO and ZnO. The strong peaks of the Cu, Zn, and O elements are exhibited in the EDX spectrum. The FTIR spectra appear at around 3385 cm−1 and 1637 cm−1, caused by O–H stretching, and 400 cm−1 to 590 cm−1, ascribable to Zn–O stretching. The photocatalytic performances of CuO/ZnO nanocomposites are investigated for the degradation of methylene blue (MB) aqueous solution in direct solar irradiation. The degradation value of MB with 5 wt % CuO/ZnO is measured to be 98%, after 2 h of solar irradiation. The reactive •O2− and •OH radicals play important roles in the photodegradation of MB. Mineralization of MB is around 91% under sunlight irradiation within 7 h. The photodegradation treatment for the textile wastewater using sunlight is an easy technique—simply handled, and economical. Therefore, the solar photodegradation technique may be a very effective method for the treatment of wastewater instead of photodegradation with the artificial and expensive Hg-Xe lamp.
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Zhu, Hua, Li Li, Wei Zhou, Zongping Shao e Xianjian Chen. "Advances in non-enzymatic glucose sensors based on metal oxides". Journal of Materials Chemistry B 4, n.º 46 (2016): 7333–49. http://dx.doi.org/10.1039/c6tb02037b.
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Wang, Haiguang, Yongfeng Liu e Jun Zhang. "Hydrogen Production via Methanol Steam Reforming over CuO/ZnO/Al2O3 Catalysts Prepared via Oxalate-Precursor Synthesis". Catalysts 13, n.º 10 (30 de setembro de 2023): 1335. http://dx.doi.org/10.3390/catal13101335.
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CuO/ZnO/Al2O3 catalysts are commonly used for the methanol steam reforming reaction. The oxalate precursor of CuO/ZnO/Al2O3 catalysts were prepared via the co-precipitation method using oxalic acid as the precipitator, deionized water and ethanol as the solvent, and microwave radiation and water baths as aging heating methods, respectively. This suggests that ethanol selects the crystalline phase composition of oxalate precursors and limits their growth. Microwave irradiation prompted the isomorphous substitution between Cu2+ of CuC2O4 and Zn2+ of ZnC2O4 in the mother liquid; Zn2+ in ZnC2O4·xH2O was substituted with Cu2+ in CuC2O4, forming the master phase (Cu,Zn)C2O4 in the precursor. Moreover, the solid solution Cu-O-Zn formed after calcination, which exhibited nano-fibriform morphology. It has the characteristics of small CuO grains, a large surface area, and strong synergistic effects between CuO and ZnO, which is conducive to improving the catalytic performance of methanol steam reforming. The conversion rate of methanol reached 91.2%, the space time yield of H2 reached 516.7 mL·g−1·h−1, and the selectivity of CO was only 0.29%.
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OSTROVSKII, VICTORE E. "METAL-OXYGEN-HYDROGEN SOLID SYSTEM OF CONTROLLED COMPOSITION: DIFFERENTIAL HEAT EFFECTS, KINETICS, AND MECHANISMS OF THE CuO → Cu4·OH2 GRADING". International Journal of Modern Physics B 16, n.º 01n02 (20 de janeiro de 2002): 42–49. http://dx.doi.org/10.1142/s0217979202009433.
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The process of fine-crystal CuO reduction by successive small portions of H 2 was studied through isothermal calorimetric, kinetic, adsorption-desorption, and stoichiometric measurements at 293-520 K and H 2 pressures up to 100 Pa under conditions when equilibrium within the solid was achieved at any instant. The CuO studied was in the form of the component of the CuO-ZnO-Al 2 O 3 system. The stoichiometry of the copper component reduced corresponded to Cu 4· OH 2.
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Andreasen, Jens Wenzel, Frank Berg Rasmussen, Stig Helveg, Alfons Molenbroek, Kenny Ståhl, Martin Meedom Nielsen e Robert Feidenhans'l. "Activation of a Cu/ZnO catalyst for methanol synthesis". Journal of Applied Crystallography 39, n.º 2 (12 de março de 2006): 209–21. http://dx.doi.org/10.1107/s0021889806003098.
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The structural changes during activation by temperature-programmed reduction of a Cu/ZnO catalyst for methanol synthesis have been studied by severalin situtechniques. The catalyst is prepared by coprecipitation and contains 4.76 wt% Cu, which forms a substitutional solid solution with ZnO as determined by resonant X-ray diffraction.In situresonant X-ray diffraction reveals that the Cu atoms are extracted from the solid solution by the reduction procedure, forming metallic Cu crystallites. Cu is redispersed in bulk or surface Zn lattice sites upon oxidation by heating in air. The results are confirmed byin situelectron energy loss spectroscopy andin situresonant small-angle X-ray scattering. The average Cu particle size in the reduced catalyst as determined by the latter technique is ∼27 Å. The observed structural behaviour may have important implications for catalyst design and operation. More than one type of Cu particle with different origins may be present in Cu/ZnO catalysts with Cu loadings higher than the solubility limit of Cu in ZnO: particles formed by extraction of Cu from the (Zn,Cu)O solid solution and particles formed by reduction of CuO primary particles. The former type is highly dispersed and in intimate contact with the surface of the host ZnO particles. The possibility of re-forming the (Zn,Cu)O solid solution by oxidation may provide a means of redispersing Cu in a deactivated catalyst.
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Vengatesh, Priya P., J. Jeyasundari, Athithan A. S. Sakthi e A. Naveena. "Investigation of Antibacterial Activity of Ag-CuO and Ag-ZnO Nanocomposites synthesized by Chemical Precipitation Method". Research Journal of Chemistry and Environment 27`, n.º 9 (15 de agosto de 2023): 60–68. http://dx.doi.org/10.25303/2709rjce06068.
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In this present study, the synthesis of Ag-CuO and Ag-ZnO nanocomposites has been conducted. The individual Ag-CuO and Ag-ZnO nanocomposites were synthesized by using chemical precipitation method. The resulting particles were characterized by using UV-Visible, FTIR, XRD and SEM. The optical properties and band gap measurements were explored by UV-Visible spectroscopy. FTIR spectrum of the prepared nanocomposite revealed the presence of vibrational modes which were related to the Cu-O, Zn-O. The XRD analysis confirmed the structural purity of synthesized nanocomposites and the estimated crystallite size is 31.93 nm and 26.62 nm for Ag-CuO and Ag-ZnO nanocomposites respectively. The morphological features were explored by SEM analysis with deposition of Ag nanoparticles on the surface of metal oxide nanoparticles. The antibacterial activities of synthesized nanocomposites were tested on bacteria strains such as Escherichia coli (Gram -ve) and Staphylococcus aureus (Gram +ve) respectively through well diffusion method. The synthesized nanocomposite shows the higher efficacy against E.coli with an average diameter size of 17 mm zone of inhibition. This result suggests that Ag-CuO and Ag-ZnO nanocomposites can be used effectively against microbial growth. Therefore, the synthesized nanocomposite may be promising for the antibacterial agent in pharmaceutical applications.
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Liu, Jing, Yan Chen e Hongyan Zhang. "Study of Highly Sensitive Formaldehyde Sensors Based on ZnO/CuO Heterostructure via the Sol-Gel Method". Sensors 21, n.º 14 (8 de julho de 2021): 4685. http://dx.doi.org/10.3390/s21144685.
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Formaldehyde (HCHO) gas sensors with high performance based on the ZnO/CuO heterostructure (ZC) were designed, and the sensing mechanism was explored. FTIR results show that more OH− and N–H groups appeared on the surface of ZC with an increase in Cu content. XPS results show that ZC has more free oxygen radicals (O*) on its surface compared with ZnO, which will react with more absorbed HCHO molecules to form CO2, H2O and, electrons, accelerating the oxidation-reduction reaction to enhance the sensitivity of the ZC sensor. Furthermore, electrons move from ZnO to CuO in the ZC heterostructure due to the higher Fermi level of ZnO, and holes move from CuO to ZnO until the Fermi level reaches an equilibrium, which means the ZC heterostructure facilitates more free electrons existing on the surface of ZC. Sensing tests show that ZC has a low detection limit (0.079 ppm), a fast response/recovery time (1.78/2.90 s), and excellent selectivity and sensitivity for HCHO detection at room temperature. In addition, ambient humidity has little effect on the ZC gas sensor. All results indicate that the performance of the ZnO sensor for HCHO detection can be improved effectively by ZC heterojunction.
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Giraldo-Daza, Helver Augusto, José Darío Agudelo-Giraldo, César Leandro Londoño-Calderón e Henry Reyes-Pineda. "Structural Disorder of CuO, ZnO, and CuO/ZnO Nanowires and Their Effect on Thermal Conductivity". Crystals 13, n.º 6 (15 de junho de 2023): 953. http://dx.doi.org/10.3390/cryst13060953.
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In this work, the structural defects and the thermal conductivity of CuO, ZnO, and CuO/ZnO nanowires have been studied, using molecular dynamics simulation with COMB3 potential. The initial parameters and atoms positions were taken from reports of bulk materials with tenorite and wurtzite structures, respectively. Nanowires were grown along the c-axis, as observed experimentally. The results confirm the defects apparition in the systems after simulation with a formation of grains to reduce the energy of the nanowires. In the CuO nanowires case, the lack of periodicity in the basal plane causes a contraction effect over the network parameter b of the monoclinic structure with a Cu-O distance reduction. [A constriction effect on inclined planes, as a product of surface charges, deforms the nanowire, generating undulations. In ZnO nanowires, a decrease in the Zn-Zn distance produced a contraction in the nanowire length. A constriction effect was evident on the surface charges. It presented a bond reduction effect, which was larger at the ends of the nanowire. In CuO/ZnO nanowires, the structural defects come from the distortions of the crystalline lattice of the ZnO rather than CuO. The thermal conductivity of the nanowires was calculated at temperatures between 200 K and 600 K using the Green–Kubo equation. Results showed similar values to those reported experimentally, and the characteristic maximum with similar trends to those observed in semiconductors. Our results suggest that structural defects appear in nanowires grown on the free substrate, and are not related to the lattice mismatch.
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Wang, Feng, Jing Zhou, Zi Long An e Xin Jing Zhou. "Characteristic of Cu-Based Catalytic Coating for Methanol Steam Reforming Prepared by Cold Spray". Advanced Materials Research 156-157 (outubro de 2010): 68–73. http://dx.doi.org/10.4028/www.scientific.net/amr.156-157.68.
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Cu-based catalyst is active for methanol steam reforming (MSR) at low temperature. The Cu、Cu+Al2O3 composite and CuO/ZnO/Al2O3 catalytic powers are used as feedstock for coating fabrication by cold spray. MSR experiment and SEM、EDX 、XRD analysis before and after the MSR on the coating has been carried out to study the micostructure and catalytic characteristic of the deposits. Results show that, after reaction the morphology of the Cu coating changes from piled sheets structure to mciro-ramify structure, its porosity obviously increase, the net weight of O、Al in the coating increases, H2 content in the reaction products reaches 74.9%. While for the Cu+Al2O3 composite coating, the content of copper in the coating decreases compared with the initial powder, and the stability of Cu+Al2O3 coating is better than the copper coating in MSR reaction. Particle bonding between coating and substrate and the bonding between the particles in the coating is mainly belonged to mechanical bite and physical bonding; Porosity in the latter two coating is higher than the copper coating. But there is no phase change of the coating. CuO/ZnO/Al2O3 coating shows a much higher activity than conventional fixed bed catalyst due to the reduction of heat and mass transfer resistance in the reactor. So it is available to fabricate catalytic coating by cold spray.
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Shrestha, Buddha Kumar, Hira Mani Trital e Armila Rajbhandari. "Synthesis and Characterization of CuO-ZnO Nano Additive for Lubricant". Scientific World 13, n.º 13 (5 de agosto de 2020): 33–36. http://dx.doi.org/10.3126/sw.v13i13.30504.
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A mixed metal oxide (CuO-ZnO) additives has been successfully synthesized in laboratory by co-precipitation technique. The optimum ratio of CuO and ZnO in mixed metal oxide was found to be 1:1. The sodium lauryl sulfate (SLS) has been used as surfactant. The obtained material was found to be crystalline having crystalline size of 18 nm. The stretching band in FTIR spectra at around 1072 cm-1 to 750 cm-1 and around 600 cm-1 indicates the presence of Zn-O and Cu-O bonds. As prepared nano-particles have been used as nano additive in base oil to improve physio-chemical parameters of lubricants. The results revealed that the additive blended base oil (lubricant) has shown excellent lubrication properties. The higher kinematic viscosity of 33.0504 and 6.0158 at 40°C and 100°C respectively showed that as prepared additive blended lubricant is of ISO-32 category according to ISO grading system for lubricants. Similarly, viscosity index was found to be improved from 101 to 129. The pour point was found to be significantly decreased from -6°C to -24°C. So it can be used as good pour point depressant and could be used even in the extreme cold environment condition. The flash point was found to be increased from 215°C to 220°C indicating that the prepared mixed metal oxide (CuO-ZnO) acts as flash point enhancer. The copper strip corrosion rating was found to be 1b for additive indicating the non corrosive nature. The absence of moisture and pH around the neutral range 6.18 showed the additive blended lubricant is not harmful for machinery devices.
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Mokhtari, S., e A. W. Wren. "Investigating the effect of Copper Addition on SiO2-ZnO-CaO-SrO-P2O5 Glass Polyalkenoate Cements: Physical, Mechanical and Biological Behavior". Biomedical Glasses 5, n.º 1 (1 de fevereiro de 2019): 13–33. http://dx.doi.org/10.1515/bglass-2019-0002.
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Abstract The physical, mechanical, and biological behaviour of copper containing glass polyalkenotare cements were investigated, where copper (Cu2+) was incorporated into a SiO2-ZnO-CaO-SrO-P2O5 based glass system. Three GPCs were formulated for this study, a Control and two Cu-GPCs with 6 (Cu-1) and 12 (Cu-2) Mol.% of CuO substituted for the SiO2 in the glass. Rheological evaluation of GPCs determined that the addition of the Cu decreases the working and setting times in the cements. The mechanical properties of the cements were evaluated after 1 - 21 days incubation in DI water. The compressive strength of the cements were found to range between 21-36 MPa, with Cu-1 having the highest compressive strength. Biaxial flexural strength and Shear Bond Strength of the GPCs were found to increase with respect to time and were higher for the Cu-GPCs at 14 MPa and 2.1 MPa respectively. Bioactivity testing was conducted using Simulated Body Fluid (SBF) which revealed CaP precipitants on each of the GPCs surfaces. The effect o f Cu addition to the GPCs greatly enhanced the antibacterial inhibition zone (IZ) when tested in E.coli (3mm), S.aureus (24mm) and S.epidermidis (22mm). Cytocompatibility testing revealed more favorable MC3T3 osteoblast cell viability when compared to the Control GPC.
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Deore, M. K., V. B. Gaikwad, D. D. Kajale e J. H. Jain. "Effect of Surface Modification by CuO on Surface Morphology, Electrical Properties and Gas Response of ZnO Thick Films". Sensor Letters 17, n.º 12 (1 de dezembro de 2019): 968–76. http://dx.doi.org/10.1166/sl.2019.4182.
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The screen printing technique was used for the preparation of ZnO thick films. The films were dipped into 0.01 M aq. solution of (CulCl2 · 2H2O) for 10, 15, 20 and 30 min time interval for the surface modification. The dispersed CuCl2 on the film surface oxidized during heating at 500 °C and converted into CuO. SEM coupled with EDAX analysis showed the morphology of surface and elemental composition of the films. The micrographs of the films dipped at different time interval show the very interesting changes. The EDAX result shows variation in Zn/O and Cu/Zn ratio with different concentration of Cu. The toxic gases such as Cl2, H2S, CO and LPG etc. were used to study the gas response of the films at different temperatures. The pure film shows the poor response to H2S gas at 300 °C while surface modified film shows a good response to the same gas at 100 °C temperature for 100 ppm level gas concentration. The main characteristics of the films such as the selectivity, response and recovery time were studied and are presented in this paper.
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Izaki, Masanobu, Pei Loon Khoo e Tsutomu Shinagawa. "Review—Solution Electrochemical Process for Fabricating Metal Oxides and the Thermodynamic Design". Journal of The Electrochemical Society 168, n.º 11 (1 de novembro de 2021): 112510. http://dx.doi.org/10.1149/1945-7111/ac371a.
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Electrochemical processes in aqueous solutions are widely used for preparation of metals, alloys, composites, metal oxides and compounds. For understanding and designing an electrochemical process, it is crucial to study its soluble chemical species, potential-pH diagram, and solubility curves drawn based on thermodynamics. In this review, equilibrium electrode potentials, critical pH values, and dissolved chemical species related to the oxidation-reduction, acid-base, and ligand-exchanging reactions, in addition to the calculation based on standard Gibbs free energy are first briefly mentioned. This is followed by the description of the change in equilibrium electrode potentials of metal and metal compounds as demonstrated in the electrochemical preparation of the Cu–In–Se precursor for the Cu(In,Ga)Se2 solar cell application. Additionally, the advantages and usefulness of soluble chemical species, potential-pH diagram, and solubility curves are discussed, by giving examples of direct electrodepositions of metal oxides, the chemical introduction of impurities into ZnO enabling characteristic control, the chemical bath deposition process (CBD) for Zn(S,O,OH) buffer layer in Cu(In,Ga)Se2 solar cell, and lastly, the design of the electrochemical process for fabricating CuO/Cu2O bilayers.
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王, 鑫. "Preparation of CuO/Cu2O/ZnO Composite and Study on the Catalytic Performance of Fenton under Visible Light". Hans Journal of Nanotechnology 11, n.º 03 (2021): 43–53. http://dx.doi.org/10.12677/nat.2021.113006.
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Roberts, Andrew C., Lee A. Groat, Joel D. Grice, Robert A. Gault, Martin C. Jensen, Elizabeth A. Moffatt e John A. R. Stirling. "Leisingite, Cu(Mg,Cu,Fe,Zn)2Te6+O6·6H2O, a new mineral species from the Centennial Eureka mine, Juab County, Utah". Mineralogical Magazine 60, n.º 401 (agosto de 1996): 653–57. http://dx.doi.org/10.1180/minmag.1996.060.401.11.
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AbstractLeisingite, ideally Cu(Mg,Cu,Fe,Zn)2Te6+O6·6H2O, is hexagonal, P3 (143), with unit-cell parameters refined from powder data: a = 5.305(1), c = 9.693(6) Å, V = 236.2(2) Å3, c/a = 1.8271, Z = 1. The strongest six reflections of the X-ray powder-diffraction pattern [d in Å (I) (hkl)] are: 9.70 (100) (001), 4.834 (80) (002), 4.604 (60) (100), 2.655 (60) (110), 2.556 (70) (111) and 2.326 (70) (112). The mineral is found on the dumps of the Centennial Eureka mine, Juab County, Utah U.S.A. where it occurs as isolated, or rarely as clusters of, hexagonal-shaped very thin plates or foliated masses in small vugs of crumbly to drusy white to colourless quartz. Associated minerals are jensenite, cesbronite and hematite. Individual crystals are subhedral to euhedral and average less than 0.1 mm in size. Cleavage {001} perfect. Forms are: {001} major; {100}, {110} minute. The mineral is transparent to somewhat translucent, pale yellow to pale orange-yellow, with a pale yellow streak and an uneven fracture. Leisingite is vitreous with a somewhat satiny to frosted appearance, brittle to somewhat flexible and nonfluorescent; H(Mohs) 3–4; D(calc.) 3.41 for the idealized formula; uniaxial negative, ω = 1.803(3), ɛ = 1.581 (calc.). Averaged electron-microprobe analyses yielded CuO 24.71, FeO 6.86, MgO 6.19, ZnO 0.45, TeO3 36.94, H2O (calc.) [21.55], total [96.70] wt.%, leading to the empirical formula based on O = 12. The infrared absorption spectrum shows definite bands for structural H2O with an O-H stretching frequency centered at 3253 cm−1 and a H-O-H flexing frequency centered at 1670 cm−l. The mineral name honours Joseph F. Leising, Reno, Nevada, who helped collect the discovery specimens.
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Kuklin, Mikhail S., e Antti J. Karttunen. "Evolutionary Algorithm-Based Crystal Structure Prediction of CuxZnyOz Ternary Oxides". Molecules 28, n.º 16 (10 de agosto de 2023): 5986. http://dx.doi.org/10.3390/molecules28165986.
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Binary zinc(II) oxide (ZnO) and copper(II) oxide (CuO) are used in a number of applications, including optoelectronic and semiconductor applications. However, no crystal structures have been reported for ternary Cu-Zn-O oxides. In that context, we investigated the structural characteristics and thermodynamics of CuxZnyOz ternary oxides to map their experimental feasibility. We combined evolutionary crystal structure prediction and quantum chemical methods to investigate potential CuxZnyOz ternary oxides. The USPEX algorithm and density functional theory were used to screen over 4000 crystal structures with different stoichiometries. When comparing compositions with non-magnetic CuI ions, magnetic CuII ions, and mixed CuI-CuII compositions, the magnetic Cu2Zn2O4 system is thermodynamically the most favorable. At ambient pressures, the thermodynamically most favorable ternary crystal structure is still 2.8 kJ/mol per atom higher in Gibbs free energy compared to experimentally known binary phases. The results suggest that thermodynamics of the hypothetical CuxZnyOz ternary oxides should also be evaluated at high pressures. The predicted ternary materials are indirect band gap semiconductors.
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Kampf, A. R., S. J. Mills e B. P. Nash. "Pauladamsite, Cu4(SeO3)(SO4)(OH)4·2H2O, a new mineral from the Santa Rosa mine, Darwin district, California, USA". Mineralogical Magazine 80, n.º 6 (outubro de 2016): 949–58. http://dx.doi.org/10.1180/minmag.2016.080.032.
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AbstractPauladamsite (IMA2015-005), Cu4(SeO3)(SO4)(OH)4·2H2O, is a new mineral from the Santa Rosa mine, Darwin district, Inyo County, California, USA, where it occurs as a secondary oxidation-zone mineral in association with brochantite, chalcanthite, gypsum, ktenasite, mimetite, schulenbergite and smithsonite on limonitic gossan. Pauladamsite forms green, multiply twinned blades up to 0.5 mm long grouped in radial sprays. The streak is pale green. Crystals are transparent and have vitreous to silky lustre. The Mohs hardness is ∼2, the tenacity is brittle, the fracture is irregular and crystals exhibit one perfect cleavage on [001]. The calculated density is 3.535 g/cm3. Electron microprobe analyses provided: CuO 48.96, ZnO 3.56, SeO2 18.82, SO3 13.90, H2O 13.29 (calc.), total 98.53 wt.%. The empirical formula (based on 13 O apfu) is: (Cu3.55Zn0.25)∑3.80Se0.98SO13H8.50. Pauladamsite is triclinic, P1, a = 6.0742(7), b = 8.4147(11), c = 10.7798 (15) Å, α = 103.665(7), β = 95.224(7), γ = 90.004(6)°, V = 533.03(12) Å3 and Z = 2. The eight strongest lines in the powder X-ray diffraction pattern are [dobs in Å(I)(hkl)]: 10.5(46)(011); 3.245(100)(001); 5.81(50)(011); 2.743(49)(112); 3.994(67)(012); 3.431(23)(1̄12,1̄2̄1,1̄20); 2.692(57)(03̄2,1̄22,2̄1̄2); and 2.485(39)(21̄2,1̄3̄2,02̄4). The structure of pauladamsite (R1 = 10.6% for 2086 Fo > 4σF) contains Cu2+O6 octahedra, SO4 tetrahedra and Se4+O3 pyramids. There are four different CuO6 octahedra, each of which exhibits typical Jahn-Teller distortion, with four short equatorial Cu–O bonds and two much longer apical Cu–O bonds. The CuO6 octahedra share edges to form five-octahedra-wide bands extending along [100]. Adjacent bands are connected in the [011̄] direction by bridging SO4 tetrahedra and in the [011] direction by bridging Se4+O3 pyramids, thereby forming a framework.
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Pekov, I. V., N. V. Zubkova, M. E. Zelenski, V. O. Yapaskurt, Yu S. Polekhovsky, O. A. Fadeeva e D. Yu Pushcharovsky. "Yaroshevskite, Cu9O2(VO4)4Cl2, a new mineral from the Tolbachik volcano, Kamchatka, Russia". Mineralogical Magazine 77, n.º 1 (fevereiro de 2013): 107–16. http://dx.doi.org/10.1180/minmag.2013.077.1.10.
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AbstractA new mineral, yaroshevskite, ideally Cu9O2(VO4)4Cl2, occurs in sublimates collected from the Yadovitaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with euchlorine, fedotovite, hematite, tenorite, lyonsite, melanothallite, atlasovite, kamchatkite and secondary avdoninite, belloite and chalcanthite. Yaroshevskite forms isolated prismatic crystals, up to 0.1 × 0.15 × 0.3 mm in size, on the surface of euchlorine crusts. The mineral is opaque and black, with a reddish black streak and lustre between metallic and adamantine. Yaroshevskite is brittle, no cleavage was observed and the fracture is uneven. The Mohs hardness is ~3½ (corresponding to a mean VHN micro-indentation hardness of 172 kg mm -2) and the calculated density is 4.26 g cm-3. In reflected light, yaroshevskite is grey with a weak bluish hue. Pleochroism, internal reflections and bireflectance were not observed. Anisotropy is very weak. The composition (wt.%) determined by electron microprobe is: CuO 61.82, ZnO 0.53, Fe2O3 0.04, V2O531.07, As2O50.32, MoO3 1.56, Cl 6.23, O=Cl2 1.41; total 100.16. The empirical formula, calculated on the basis of 20 (O + Cl) anions is (Cu8.80 Zn0.07 Fe0.01)Σ 8.88(V3.87Mo0.12As0.03)σ 4.02O18.01Cl1.99. Yaroshevskite is triclinic, space group P, a = 6.4344(11), b = 8.3232(13), c = 9.1726(16) Å , α = 105.338(14), β = 96.113(14), γ = 107.642(1)°, V = 442.05(13) Å3 and Z = 1. The nine strongest reflections in the X-ray powder pattern [dobs in Å (I)(hkl)] are as follows: 8.65(100)(001); 6.84(83)(01); 6.01(75)(100); 5.52(60)(01); 4.965(55)(011); 4.198(67)(1); 4.055(65)(110); 3.120(55)(021); 2.896(60)(21,003,20). The crystal structure was solved by direct methods from single-crystal X-ray diffraction data and refined to R = 0.0737. The yaroshevskite structure is unique. It is based on corrugated layers made up of chains of edge-sharing flat squares with central Cu2+ cations [Cu(1), Cu(4) and Cu(5)]; neighbouring chains are connected via groups consisting of three Cu2+ -centred squares [two Cu(3) and Cu(6)]. Neighbouring layers are connected via pairs of Cu(2)O4Cl five-coordinate polyhedra and isolated VO4 tetrahedra. The structure of yaroshevskite can also be considered in terms of oxygen-centred tetrahedra: O(7)Cu4 tetrahedra are connected via common Cu(4) and Cu(5) vertices to form pyroxene-like chains [O2Cu6]∞. In this context, the structural formula can be written Cu3[O2Cu6][VO4]4Cl2. The mineral name honours the Russian geochemist Alexei A. Yaroshevsky (b. 1934) of Moscow State University.
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Pekov, Igor, Fedor Sandalov, Natalia Koshlyakova, Marina Vigasina, Yury Polekhovsky, Sergey Britvin, Evgeny Sidorov e Anna Turchkova. "Copper in Natural Oxide Spinels: The New Mineral Thermaerogenite CuAl2O4, Cuprospinel and Cu-Enriched Varieties of Other Spinel-Group Members from Fumaroles of the Tolbachik Volcano, Kamchatka, Russia". Minerals 8, n.º 11 (1 de novembro de 2018): 498. http://dx.doi.org/10.3390/min8110498.
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This paper is the first description of natural copper-rich oxide spinels. They were found in deposits of oxidizing-type fumaroles related to the Tolbachik volcano, Kamchatka, Russia. This mineralization is represented by nine species with the following maximum contents of CuO (wt.%, given in parentheses): a new mineral thermaerogenite, ideally CuAl2O4 (26.9), cuprospinel, ideally CuFe3+2O4 (28.6), gahnite (21.4), magnesioferrite (14.7), spinel (10.9), magnesiochromite (9.0), franklinite (7.9), chromite (5.9), and zincochromite (4.8). Cuprospinel, formerly known only as a phase of anthropogenic origin, turned out to be the Cu-richest natural spinel-type oxide [sample with the composition (Cu0.831Zn0.100Mg0.043Ni0.022)Σ0.996(Fe3+1.725Al0.219Mn3+0.048Ti0.008)Σ2.000O4 from Tolbachik]. Aluminum and Fe3+-dominant spinels (thermaerogenite, gahnite, spinel, cuprospinel, franklinite, and magnesioferrite) were deposited directly from hot gas as volcanic sublimates. The most probable temperature interval of their crystallization is 600–800 °C. They are associated with each other and with tenorite, hematite, orthoclase, fluorophlogopite, langbeinite, calciolangbeinite, aphthitalite, anhydrite, fluoborite, sylvite, halite, pseudobrookite, urusovite, johillerite, ericlaxmanite, tilasite, etc. Cu-bearing spinels are among the latest minerals of this assemblage: they occur in cavities and overgrow even alkaline sulfates. Cu-enriched varieties of chrome-spinels (magnesiochromite, chromite, and zincochromite) were likely formed in the course of the metasomatic replacement of a magmatic chrome-spinel in micro-xenoliths of ultrabasic rock under the influence of volcanic gases. The new mineral thermaerogenite, ideally CuAl2O4, was found in the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption. It forms octahedral crystals up to 0.02 mm typically combined in open-work clusters up to 1 mm across. Thermaerogenite is semitransparent to transparent, with a strong vitreous lustre. Its colour is brown, yellow-brown, red-brown, brown-yellow or brown-red. The mineral is brittle, with the conchoidal fracture, cleavage is none observed. D(calc.) is 4.87 g/cm3. The chemical composition of the holotype (wt.%, electron microprobe) is: CuO 25.01, ZnO 17.45, Al2O3 39.43, Cr2O3 0.27, Fe2O3 17.96, total 100.12 wt.%. The empirical formula calculated on the basis of 4 O apfu is: (Cu0.619Zn0.422)Σ1.041(Al1.523Fe3+0.443Cr0.007)Σ1.973O4. The mineral is cubic, Fd-3m, a = 8.093(9) Å, V = 530.1(10) Å3. Thermaerogenite forms a continuous isomorphous series with gahnite. The strongest lines of the powder X-ray diffraction pattern of thermaerogenite [d, Å (I, %) (hkl)] are: 2.873 (65) (220), 2.451 (100) (311), 2.033 (10) (400), 1.660 (16) (422), 1.565 (28) (511) and 1.438 (30) (440).
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Nazarchuk, Evgeny V., Oleg I. Siidra, Diana O. Nekrasova, Vladimir V. Shilovskikh, Artem S. Borisov e Evgeniya Y. Avdontseva. "Glikinite, Zn3O(SO4)2, a new anhydrous zinc oxysulfate mineral structurally based on OZn4 tetrahedra." Mineralogical Magazine 84, n.º 4 (30 de abril de 2020): 563–67. http://dx.doi.org/10.1180/mgm.2020.33.
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AbstractA new mineral glikinite, ideally Zn3O(SO4)2, was found in high-temperature exhalative mineral assemblages in the Arsenatnaya fumarole, Second scoria cone of the Great Tolbachik Fissure Eruption (1975–1976), Tolbachik volcano, Kamchatka Peninsula, Russia. Glikinite is associated closely with langbeinite, lammerite-β, bradaczekite, euchlorine, anhydrite, chalcocyanite and tenorite. It is monoclinic, P21/m, a = 7.298(18), b = 6.588(11), c = 7.840(12) Å, β = 117.15(3)°, V = 335.4(11) Å3 and R1 = 0.046. The eight strongest lines of the powder X-ray diffraction pattern [d in Å (I) (hkl)] are: 6.969(56)(00$\bar{1}$), 3.942(52)(101), 3.483(100)(00$\bar{2}$), 3.294(49)(020), 2.936(43)(120), 2.534(63)(201), 2.501(63)(20$\bar{3}$) and 2.395(86)(02$\bar{2}$). The chemical composition determined by electron-microprobe analysis is (wt.%): ZnO 42.47, CuO 19.50, SO3 39.96, total 101.93. The empirical formula calculated on the basis of O = 9 apfu is Zn2.07Cu0.97S1.98O9 and the simplified formula is Zn3O(SO4)2. Glikinite is a Zn,Cu analogue of synthetic Zn3O(SO4)2. The crystal structure of glikinite is based on OZn4 tetrahedra sharing common corners, thus forming [Zn3O]4+ chains. Sulfate groups interconnect [Zn3O]4+ chains into a 3D framework.
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Siidra, Oleg I., Evgeny V. Nazarchuk, Anatoly N. Zaitsev, Yury S. Polekhovsky, Thomas Wenzel e John Spratt. "Dokuchaevite, Cu8O2(VO4)3Cl3, a new mineral with remarkably diverse Cu2+ mixed-ligand coordination environments". Mineralogical Magazine 83, n.º 5 (24 de junho de 2019): 749–55. http://dx.doi.org/10.1180/mgm.2019.41.
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AbstractDokuchaevite, ideally Cu8O2(VO4)3Cl3, was found in the Yadovitaya fumarole of the Second scoria cone of the North Breach of the Great Tolbachik Fissure Eruption (1975–1976), Tolbachik volcano, Kamchatka Peninsula, Russia. Dokuchaevite occurs on the crusts of various copper sulfate exhalative minerals (such as kamchatkite and euchlorine) as individual prismatic crystals. Dokuchaevite is triclinic, P$\bar{1}$, a = 6.332(3), b = 8.204(4), c = 15.562(8) Å, α = 90.498(8), β = 97.173(7), γ = 90.896(13)°, V = 801.9(7) Å3 and R1 = 0.057. The eight strongest lines of the X-ray powder diffraction pattern are (d, Å (I)(hkl): (15.4396)(18)(00$\bar{1}$), (7.2762)(27)(0$\bar{1}$1), (5.5957)(43)(012), (4.8571)(33)($\bar{1}\bar{1}$1), (3.1929) (29)(023), (2.7915)(30)(202), (2.5645)(21)(032), (2.5220)(100)(1$\bar{3}$0), (2.4906)(18)(130) and (2.3267)(71)(2$\bar{2}$2). The chemical composition determined by electron-microprobe analysis is (wt.%): CuO 60.87, ZnO 0.50, FeO 0.36, V2O5 19.85, As2O5 6.96, SO3 0.44, MoO3 1.41, SiO2 0.20, P2O5 0.22, Cl 10.66, –O = Cl2 2.41, total 99.06. The empirical formula calculated on the basis of 17 anions per formula unit is (Cu7.72Zn0.06Fe0.05)Σ7.83(V2.20As0.61Mo0.10S0.06P0.03Si0.03)Σ3.03O13.96Cl3.04.The crystal structure of dokuchaevite represents a new structure type with eight Cu sites, which demonstrate the remarkable diversity of Cu2+ mixed-ligand coordination environments. The crystal structure of dokuchaevite is based on OCu4 tetrahedra that share common corners thus forming [O2Cu6]8+ single chains. Two of the eight symmetrically independent copper atoms do not form Cu–O bonds with additional oxygen atoms, and thus are not part of the OCu4 tetrahedra, but provide the three-dimensional integrity of the [O2Cu6]8+ chains into a framework. TO4 mixed tetrahedral groups are located within the cavities of the framework. The structural formula of dokuchaevite can be represented as Cu2[Cu6O2](VO4)3Cl3.
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Krause, W., H. J. Bernhardt, R. S. W. Braithwaite, U. Kolitsch e R. Pritchard. "Kapellasite, Cu3Zn(OH)6CI2, a new mineral from Lavrion, Greece, and its crystal structure". Mineralogical Magazine 70, n.º 3 (junho de 2006): 329–40. http://dx.doi.org/10.1180/0026461067030336.
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AbstractKapellasite, Cu3Zn(OH)6Cl2, is a new secondary mineral from the Sounion No. 19 mine, Kamariza, Lavrion, Greece. It is a polymorph of herbertsmithite. Kapellasite forms crusts and small aggregates up to 0.5 mm, composed of bladed or needle-like indistinct crystals up to 0.2 mm long. The colour is green-blue, the streak is light green-blue. There is a good cleavage parallel to ﹛0001﹜. Kapellasite is uniaxial negative, ω = 1.80(1), ε = 1.76(1); pleochroism is distinct, with E = pale green, O = green-blue. Dmeas = 3.55(10) g/cm3; Dcalc. = 3.62 g/cm3. Electron microprobe analyses of the type material gave CuO 58.86, ZnO 13.92, NiO 0.03, CoO 0.03, Fe2O3 0.04, Cl 16.70, H2O (calc.) 12.22, total 101.80, less O = Cl 3.77, total 98.03 wt.%. The empirical formula is (Cu3.24Zn0.75)Σ3.99(OH)5.94Cl2.06, based on 8 anions. The five strongest XRD lines are [d in Å (I/I0, hkl)] 5.730 (100, 001), 2.865 (11, 002), 2.730 (4, 200), 2.464 (9, 021/201), 1.976 (5, 022/202). Kapellasite is trigonal, space group Pml, unit-cell parameters (from single-crystal data) a = 6.300(1), c = 5.733(1) Å, V= 197.06(6) Å3, Z = 1. The crystal structure of kapellasite is based on brucite-like sheets parallel to (0001), built from edge-sharing distorted M(OH,Cl)6 (M = Cu, Zn) octahedra. The sheets stack directly on each other (…AAA… stacking). Bonding between adjacent sheets is only due to weak hydrogen and O…C1 bonds. The name is in honour of Christo Kapellas (1938–2004), collector and mineral dealer from Kamariza, Lavrion, Greece.
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Nazarchuk, Evgeny V., Oleg I. Siidra, Atali A. Agakhanov, Evgeniya A. Lukina, Evgeniya Y. Avdontseva e Gennady A. Karpov. "Itelmenite, Na2CuMg2(SO4)4, a new anhydrous sulfate mineral from the Tolbachik volcano". Mineralogical Magazine 82, n.º 6 (15 de maio de 2018): 1233–41. http://dx.doi.org/10.1180/minmag.2017.081.089.
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ABSTRACTItelmenite, ideally Na2CuMg2(SO4)4, was found in a fumarole of the Naboko scoria cone of the Tolbachik volcano Fissure Eruption (2012–2013), Kamchatka Peninsula, Russia. Itelmenite occurs as irregularly shaped grains as well as microcrystalline masses associated with anhydrite, saranchinaite, hermannjahnite, euchlorine, thénardite, aphthitalite and hematite. Itelmenite is orthorhombic, Pbca, a = 9.568(2) Å, b = 8.790(2) Å, c = 28.715(8) Å, V = 2415.0(11) Å3 and Z = 4 (from single-crystal diffraction data). The nine strongest lines of the powder X-ray diffraction pattern are [d(I)(hkl)]: 7.9614(41)(102), 7.1803(32)(004), 5.9122(64)(112), 3.8455(87)(122), 3.6292(52)(214), 3.3931(62)(215), 3.0003(44)(027), 2.9388(100)(312) and 2.4975(56)(230). The chemical composition determined by the electron-microprobe analysis is (wt.%): Na2O 10.77, K2O 0.20, MgO 11.10, CuO 15.38, ZnO 5.61, SO3 56.42, total 99.48. The empirical formula based on O = 32 apfu is (Na3.93K0.05)Σ3.98Mg3.12(Cu2.19Zn0.78)Σ2.97S7.97O32. The simplified formula is Na2CuMg2(SO4)4 taking into account structural data. The crystal structure was solved by direct methods and refined to an agreement index R1 = 0.034 on the basis of 1855 independent observed reflections. The structure of itelmenite is based on a unique type of [A2+3(SO4)4]2– (A = Mg, Cu and Zn) heteropolyhedral framework with voids filled by Na+ cations.
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Pekov, Igor V., Natalia V. Zubkova, Vasiliy O. Yapaskurt, Dmitry I. Belakovskiy, Marina F. Vigasina, Evgeny G. Sidorov e Dmitry Yu Pushcharovsky. "New arsenate minerals from the Arsenatnaya fumarole, Tolbachik volcano, Kamchatka, Russia. III. Popovite, Cu5O2(AsO4)2". Mineralogical Magazine 79, n.º 1 (fevereiro de 2015): 133–43. http://dx.doi.org/10.1180/minmag.2015.079.1.11.
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AbstractThe new mineral popovite, Cu5O2(AsO4)2, was found in the sublimates of the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with ericlaxmanite, kozyrevskite, urusovite, lammerite, lammerite-β, johillerite, bradaczekite, tenorite, hematite, aphthitalite, anhydrite, langbeinite, calciolangbeinite, As-bearing orthoclase, etc. Popovite occurs as prismatic or tabular crystals and as grains up to 0.2 mm in size forming clusters up to 1.5 mm in size and as crusts on basalt scoria or on aphthitalite incrustations. Popovite is transparent with a vitreous to greasy lustre. Its colour is olive green to dark olive-green, but fine-grained varieties are light yellow-green. The mineral is brittle, with Mohs' hardness ∼3½. Cleavage was not observed and the fracture is uneven. Dcalc is 5.30 g cm–3. Popovite is optically biaxial (+), α = 1.84(1), β ≈ 1.86, γ = 1.96(1), 2Vmeas = 50(20)°. The Raman spectrum is given. Chemical data (wt.%, electron-microprobe) are CuO 63.28, ZnO 0.56, V2O50.12, As2O5 35.80, SO3 0.27, total 100.03. The empirical formula, based on 10 O a.p.f.u., is (Cu4.99Zn0.04)Σ5.03(As1.95S0.02V0.01)Σ1.98O10. Popovite is triclinic, P1̄, a = 5.1450(3), b = 6.2557(3), c = 6.2766(4) Å, α = 100.064(5), β = 96.351(5), γ = 95.100(5)°, V = 196.47(1) Å3 and Z = 1. The strongest reflections in the powder X-ray diffraction pattern [d, Å (I)(hkl)] are 3.715(36)(110, 101), 3.465(43)(11̄1), 2.968(90)(01̄2), 2.927(100)(111), 2.782(31)(1̄02), 2.768(67)(1̄20), 2.513(55)(1̄2̄1) and 2.462(67)(2̄01). Popovite has a novel structure type. Its crystal structure, solved from single-crystal X-ray diffraction data (R = 0.0459), is based on (010) layers forming an interrupted framework. The layer consists of Cu(1)O6 octahedra with very strong Jahn-Teller distortion and Cu(2)O5 and Cu(3)O5 polyhedra. The linkage between the layers is reinforced by isolated AsO4 tetrahedra. Popovite is named in honour of the Russian mineralogists Vladimir Anatol'evich Popov (b. 1941) and Valentina Ivanovna Popova (b. 1941), a husband and wife research team working in the Institute of Mineralogy of the Urals Branch of the Russian Academy of Sciences, Miass, Russia.
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Siidra, Oleg I., Evgeny V. Nazarchuk, Anatoly N. Zaitsev e Vladimir V. Shilovskikh. "Majzlanite, K2Na(ZnNa)Ca(SO4)4, a new anhydrous sulfate mineral with complex cation substitutions from Tolbachik volcano". Mineralogical Magazine 84, n.º 1 (22 de outubro de 2019): 153–58. http://dx.doi.org/10.1180/mgm.2019.68.
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AbstractA new mineral majzlanite, ideally K2Na(ZnNa)Ca(SO4)4, was found in high-temperature exhalative mineral assemblages in the Yadovitaya fumarole, Second scoria cone of the Great Tolbachik Fissure Eruption (1975–1976), Tolbachik volcano, Kamchatka Peninsula, Russia. Majzlanite is associated closely with langbeinite and K-bearing thénardite. Majzlanite is grey with a bluish tint, has a white streak and vitreous lustre. The mineral is soluble in warm water. Majzlanite is monoclinic, C2/c, a = 16.007(2), b = 9.5239(11), c = 9.1182(10) Å, β = 94.828(7)°, V = 1385.2(3) Å3 and Z = 16. The eight strongest lines of the X-ray powder diffraction pattern are [d, Å (I, %)(hkl)]: 3.3721(40)($\bar{3}$12), 3.1473(56)($\bar{4}$02), 3.1062(65)($\bar{2}$22), 2.9495(50)($\bar{1}$31), 2.8736(100)($\bar{1}$13), 2.8350(70)(421), 2.8031(45)(511) and 2.6162(41)($\bar{5}$12). The following structural formula was obtained: K2Na(Zn0.88Na0.60Cu0.36Mg0.16)(Ca0.76Na0.24)(S0.98Al0.015Si0.005O4)4. The chemical composition determined by electron-microprobe analysis is (wt.%): Na2O 9.73, K2O 15.27, ZnO 11.20, CaO 7.03, CuO 4.26, MgO 1.07, Al2O3 0.47, SO3 51.34, SiO2 0.12, total 100.49. The empirical formula calculated on the basis of 16 O apfu is K1.99Na1.93Zn0.84Ca0.77Cu0.33Mg0.16(S3.94Al0.06Si0.01)O16 and the simplified formula is K2Na(Zn,Na,Cu,Mg)Σ2(Ca,Na)(SO4)4. No natural or synthetic compounds directly chemically and/or structurally related to majzlanite are known to date. The topology of the heteropolyhedral framework in majzlanite is complex. An interesting feature of the structure of majzlanite is an edge-sharing of ZnO6 octahedra with SO4 tetrahedra.
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Pekov, Igor V., Natalia V. Zubkova, Vasiliy O. Yapaskurt, Yury S. Polekhovsky, Marina F. Vigasina, Dmitry I. Belakovskiy, Sergey N. Britvin, Evgeny G. Sidorov e Dmitry Y. Pushcharovsky. "New arsenate minerals from the Arsenatnaya fumarole, Tolbachik volcano, Kamchatka, Russia. VI. Melanarsite, K3Cu7Fe3+O4(AsO4)4". Mineralogical Magazine 80, n.º 5 (agosto de 2016): 855–67. http://dx.doi.org/10.1180/minmag.2016.080.027.
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AbstractThe new mineral melanarsite, K3Cu7Fe3+O4(AsO4)4, was found in the sublimates of the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka Peninsula, Russia. It is associated with dmisokolovite, shchurovskyite, bradaczekite, hematite, tenorite, aphthitalite, johillerite, arsmirandite, As-bearing orthoclase, hatertite, pharmazincite, etc. Melanarsite occurs as tabular to prismatic crystals up to 0.4 mm, separate or combined in clusters up to 1 mm across or in interrupted crusts up to 0.02 cm × 1 cm × 1 cm covering basalt scoria. The mineral is opaque, black, with a vitreous lustre. Melanarsite is brittle. Mohs' hardness is ∼4 and the mean VHN = 203 kg mm–2. Cleavage was not observed and the fracture is uneven. Dcalc is 4.39 g cm–3. In reflected light, melanarsite is dark grey. Bireflectance is weak, anisotropism is very weak. Reflectance values [R1–R2, % (λ, nm)] are 10.5–9.4 (470), 10.0–8.9 (546), 9.7–8.7 (589), 9.5–8.6 (650). The Raman spectrum is reported. Chemical composition (wt.%, electron microprobe) is K2O 10.70, CaO 0.03, CuO 45.11, ZnO 0.24, Al2O3 0.32, Fe2O3 6.11, TiO2 0.12, P2O5 0.07, As2O5 36.86, total 99.56. The empirical formula, based on 20 O apfu, is (K2.81Ca0.01)∑2.82(Cu7.02Fe3+0.95Al0.08Zn0.04Ti0.02)∑8.11(As3.97P0.01)∑3.98O20. Melanarsite is monoclinic, C2/c, a = 11.4763(9), b = 16.620(2), c = 10.1322(8) Å, β = 105.078(9)°, V = 1866.0(3) Å3 and Z = 4. The strongest reflections of the powder X-ray diffraction pattern [d,Å(I)(hkl)] are 9.22(100)(110), 7.59(35)(1₃11), 6.084(17) (111), 4.595(26)(1₃31, 220, 2₃21), 3.124(22)(3₃31, 1₃51), 2.763(20)(400, 1₃52), 2.570(23)(043) and 2.473(16) (260, 2₃61, 350). Melanarsite has a novel structure type. Its crystal structure, solved from single-crystal X-ray diffraction data (R = 0.091), is based upon a heteropolyhedral pseudo-framework built by distorted Cu(1–3)O6 and (Fe,Cu)O6 octahedra and As(1–3)O4 tetrahedra. Two crystallographically independent K+ cations are located in the tunnels and voids of the pseudo-framework centring eight- and seven-fold polyhedra. The name reflects the mineral being an arsenate and its black colour (from the Greek μέλαν, black).
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Pekov, I. V., N. V. Zubkova, V. O. Yapaskurt, D. I. Belakovskiy, I. S. Lykova, M. F. Vigasina, E. G. Sidorov e D. Yu Pushcharovsky. "New arsenate minerals from the Arsenatnaya fumarole, Tolbachik volcano, Kamchatka, Russia. I. Yurmarinite, Na7(Fe3+,Mg,Cu)4(AsO4)6". Mineralogical Magazine 78, n.º 4 (agosto de 2014): 905–17. http://dx.doi.org/10.1180/minmag.2014.078.4.10.
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AbstractA new mineral, yurmarinite, Na7(Fe3+,Mg,Cu)4(AsO4)6, occurs in sublimates of the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with hatertite, bradaczekite, johillerite, hematite, tenorite, tilasite and aphthitalite. Yurmarinite occurs as well-shaped, equant crystals up to 0.3 mm in size, their clusters up to 0.5 mm and thin, interrupted crystal crusts up to 3 mm × 3 mm on volcanic scoria. Crystal forms are {101}, {011}, {100}, {110} and {001}. Yurmarinite is transparent, pale green or pale yellowish green to colourless. The lustre is vitreous and the mineral is brittle. The Mohs hardness is ∼4½. One direction of imperfect cleavage was observed, the fracture is uneven. D(calc.) is 4.00 g cm−3. Yurmarinite is optically uniaxial (−), ω = 1.748(5), ε = 1.720(3). The Raman spectrum is given. The chemical composition (wt.%, electron microprobe data) is Na2O 16.85, K2O 0.97, CaO 1.28, MgO 2.33, MnO 0.05, CuO 3.17, ZnO 0.97, Al2O3 0.99, Fe2O3 16.44, TiO2 0.06, P2O5 0.12, V2O5 0.08, As2O5 56.68, total 99.89. The empirical formula, calculated on the basis of 24 O atoms per formula unit, is (Na6.55Ca0.28K0.22)S7.05(Fe2.483+Mg0.70Cu0.48Al0.23Zn0.14Ti0.01Mn0.01)S4.05(As5.94P0.02V0.01)S5.97O24. Yurmarinite is rhombohedral, Rc, a = 13.7444(2), c = 18.3077(3) Å, V = 2995.13(8) Å3, Z = 6. The strongest reflections in the X-ray powder pattern [d, Å (I)(hkl)] are: 7.28(45)(012); 4.375(33)(211); 3.440(35)(220); 3.217(36)(131,214); 2.999(30)(223); 2.841(100)(125); 2.598(43)(410). The crystal structure was solved from single-crystal X-ray diffraction data to R = 0.0230. The structure is based on a 3D heteropolyhedral framework formed by M4O18 clusters (M = Fe3+ > Mg,Cu) linked with AsO4 tetrahedra. Sodium atoms occupy two octahedrally coordinated sites in the voids of the framework. In terms of structure, yurmarinite is unique among minerals but isotypic with several synthetic compounds with the general formula (Na7–x☐x)(M3+x3+M1–x2+)(T5+O4)2 in which T = As or P, M3+ = Fe or Al, M2+ = Fe and 0 ≤ x ≤ 1. The mineral is named in honour of the Russian mineralogist, petrologist and specialist in studies of ore deposits, Professor Yuriy B. Marin (b. 1939). The paper also contains a description of the Arsenathaya fumarole and an overview of arsenate minerals formed in volcanic exhalations.
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Pekov, Igor V., Natalia N. Koshlyakova, Atali A. Agakhanov, Natalia V. Zubkova, Dmitry I. Belakovskiy, Marina F. Vigasina, Anna G. Turchkova, Evgeny G. Sidorov e Dmitry Yu Pushcharovsky. "New arsenate minerals from the Arsenatnaya fumarole, Tolbachik volcano, Kamchatka, Russia. XV. Calciojohillerite, NaCaMgMg2(AsO4)3, a member of the alluaudite group". Mineralogical Magazine 85, n.º 2 (14 de janeiro de 2021): 215–23. http://dx.doi.org/10.1180/mgm.2021.2.
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AbstractThe new alluaudite-group mineral calciojohillerite is one of the major arsenates in sublimates of the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. In middle zones of the fumarole, calciojohillerite is associated with hematite, tenorite, johillerite, nickenichite, bradaczekite, badalovite, tilasite, lammerite, ericlaxmanite, aphthitalite-group sulfates, langbeinite, calciolangbeinite, anhydrite, sanidine, fluorophlogopite, fluoborite, cassiterite, pseudobrookite, rutile, sylvite and halite. In deep zones it occurs in association with anhydrite, diopside, hematite, svabite, berzeliite, schäferite, forsterite, magnesioferrite, ludwigite, rhabdoborite-group fluoroborates, powellite, baryte, fluorapatite, udinaite, arsenudinaite and paraberzeliite. Calciojohillerite forms prismatic crystals up to 1 cm long, their aggregates and crystal crusts up to 0.5 m2. It is transparent, colourless, pale green, pale yellow, light blue, pale lilac or pink, with vitreous lustre. The mineral is brittle, with imperfect cleavage. The Mohs hardness is 3½. Dcalc is 3.915 g cm–3. Calciojohillerite is optically biaxial (–), α = 1.719(3), β = γ = 1.732(3); 2Vmeas. = 15(10)°. Chemical composition (wt.%, electron-microprobe; holotype) is: Na2O 7.32, K2O 0.10, CaO 6.82, MgO 20.31, MnO 0.68, CuO 0.27, ZnO 0.02, Al2O3 0.56, Fe2O3 3.53, TiO2 0.01, SiO2 0.03, P2O5 1.25, V2O5 0.10, As2O5 58.77, SO3 0.13, total 99.90. The empirical formula based on 12 O atoms is (Na1.30K0.01Ca0.67Mg2.78Mn0.05Cu0.02Al0.06Fe3+0.24)Σ5.13(As2.83P0.10S0.01V0.01)Σ2.95O12. Calciojohillerite is monoclinic, C2/c, a = 11.8405(3), b = 12.7836(2), c = 6.69165(16) Å, β = 112.425(3)°, V = 936.29(4) Å3 and Z = 4. The crystal structure was solved from single-crystal X-ray diffraction data, R1 = 0.0227. Calciojohillerite is isostructural with other alluaudite-group minerals. Its simplified crystal chemical formula is A(1)CaA(1)′□A(2)□A(2)′NaM(1)MgM(2)Mg2(AsO4)3 (□ = vacancy). The idealised formula is NaCaMg3(AsO4)3, or, according to the nomenclature of alluaudite-group arsenates, NaCaMgMg2(AsO4)3. Calciojohillerite is named as an analogue of johillerite NaCu2+MgMg2(AsO4)3 with species-defining Ca instead of Cu in the ideal formula.
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Pekov, I. V., N. V. Zubkova, V. O. Yapaskurt, D. I. Belakovskiy, M. F. Vigasina, E. G. Sidorov e D. Yu Pushcharovsky. "New arsenate minerals from the Arsenatnaya fumarole, Tolbachik volcano, Kamchatka, Russia. II. Ericlaxmanite and kozyrevskite, two natural modifications of Cu4O(AsO4)2". Mineralogical Magazine 78, n.º 7 (dezembro de 2014): 1553–69. http://dx.doi.org/10.1180/minmag.2014.078.7.03.
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AbstractTwo new minerals, ericlaxmanite and kozyrevskite, dimorphs of Cu4O(AsO4)2, were found in sublimates of the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. They are associated with each other and with urusovite, lammerite, lammerite-b, popovite, alarsite, tenorite, hematite, aphthitalite, langbeinite, As-bearing orthoclase, etc. Ericlaxmanite occurs as tabular, lamellar, equant or short prismatic crystals up to 0.1 mm in size, their clusters and pseudomorphs after urusovite crystal crusts up to 1.5 cm × 2 cm in area. Kozyrevskite occurs as prismatic crystals up to 0.3 mm long in clusters and as individual crystals. Both minerals are transparent with a vitreous lustre. They are brittle, with Mohs’ hardness ~3–. Ericlaxmanite is green to dark green. Kozyrevskite is bright grass green to light yellowish green; Dcalc is 5.036 (ericlaxmanite) and 4.934 (kozyrevskite) g cm–3. Both minerals are optically biaxial (–); ericlaxmanite: α = 1.870(10), β = 1.900(10), γ = 1.915(10), 2Vmeas = 60(15)º; kozyrevskite: α = 1.885(8), β = 1.895(8), γ = 1.900(8), 2Vmeas. = 75(10)º. The Raman spectra are given. Chemical data (wt.%, electron microprobe; the first value is for ericlaxmanite, the second for kozyrevskite): CuO 57.55, 58.06; ZnO 0.90, 1.04; Fe2O3 0.26, 0.12; SiO2 n.d., 0.12; P2O5 0.23, 1.23; V2O5 0.14, 0.37; As2O5 40.57, 38.78; SO3 0.17, 0.43; total 99.82, 100.15. The empirical formulae, based on 9 O a.p.f.u., are: ericlaxmanite: (Cu3.97Zn0.06Fe0.02)Σ4.05(As1.94P0.02V0.01S0.01)Σ1.98O9 and kozyrevskite: (Cu3.95Zn0.07Fe0.01)Σ4.03(As1.83P0.09S0.03V0.02Si0.01)Σ1.98O9. Ericlaxmanite is triclinic, P1̄ , a = 6.4271(4), b = 7.6585(4), c = 8.2249(3) Å , α = 98.396(4), β = 112.420(5), γ = 98.397(5)º, V = 361.11(3) Å3 and Z = 2. Kozyrevskite is orthorhombic, Pnma, a = 8.2581(4), b = 6.4026(4), c = 13.8047(12) Å , V = 729.90(9) Å3 and Z = 4. The strongest reflections in the X-ray powder patterns [d Å (I)(hkl)] are: ericlaxmanite: 3.868(46)(101), 3.685(100)(020), 3.063(71)(012), 2.957(58)(02̄ 2), 2.777(98)(2̄ 12, 2̄ 1̄ 1), 2.698(46)(2̄1̄ 2) and 2.201(51)(013, 031); kozyrevskite: 3.455(100)(004), 3.194(72)(020, 104), 2.910(69)(022), 2.732(82)(122), 2.712(87)(301) and 2.509(92)(123). Their crystal structures, solved from single-crystal X-ray diffraction data [R = 0.0358 (ericlaxmanite) and 0.1049 (kozyrevskite)], are quite different. The ericlaxmanite structure is based on an interrupted framework built by edge- and corner-sharing Cu-centred, distorted tetragonal pyramids, trigonal bipyramids and octahedra. The kozyrevskite structure is based on complicated ribbons of Cu-centred distorted tetragonal pyramids and trigonal bipyramids. Ericlaxmanite is named in honour of the Russian mineralogist, geologist, geographer, biologist and chemist Eric Laxman (1737–1796). Kozyrevskite is named in honour of the Russian geographer, traveller and military man Ivan Petrovich Kozyrevskiy (1680–1734), one of the first researchers of Kamchatka.
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Pekov, Igor V., Natalia V. Zubkova, Dmitry I. Belakovskiy, Vasiliy O. Yapaskurt, Marina F. Vigasina, Evgeny G. Sidorov e Dmitry Yu Pushcharovsky. "New arsenate minerals from the Arsenatnaya fumarole, Tolbachik volcano, Kamchatka, Russia. IV. Shchurovskyite, K2CaCu6O2(AsO4)4 and dmisokolovite, K3Cu5AlO2(AsO4)4". Mineralogical Magazine 79, n.º 7 (dezembro de 2015): 1737–53. http://dx.doi.org/10.1180/minmag.2015.079.7.02.
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AbstractTwo new minerals shchurovskyite, ideally K2CaCu6O2(AsO4)4, and dmisokolovite, ideally K3Cu5AlO2(AsO4)4, are found in sublimates of the Arsenatnaya fumarole at the Second scoriacone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka Peninsula, Russia. They are associated with one another and with johillerite, bradaczekite, tilasite, melanarsite, tenorite, hematite, aphthitalite, langbeinite, orthoclase, etc. Shchurovskyiteoccurs as coarse tabular or prismatic crystals up to 0.15 mm in size or anhedral grains forming parallel aggregates and crusts up to 1.5 cm × 2 cm across. Dmisokolovite forms tabular, prismatic or dipyramidal crystals up to 0.2 mm in size, commonly combined in clusters or crusts up to0.7 cm × 1.5 cm across. Both minerals are transparent with a vitreous lustre. They are brittle, with Mohs' hardness ≈3. Shchurovskyite is olive-green or olive drab. Dmisokolovite is bright emerald-green to light green. Dcalc = 4.28 (shchurovskyite) and 4.26 (dmisokolovite)g cm–3. Both are optically biaxial; shchurovskyite: (+), α = 1.795(5), β = 1.800(5), γ = 1.810(6), 2Vmeas = 70(15)°; dmisokolovite: (–), α = 1.758(7), β = 1.782(7), γ = 1.805(8), 2Vmeas = 85(5)°. The Ramanspectra are given. Chemical data (wt.%, electron-microprobe; first value is for shchurovskyite, second for dmisokolovite): Na2O 0.00, 0.83; K2O 8.85, 10.71; Rb2O 0.11, 0.00; MgO 0.00, 0.35; CaO 4.94, 0.21; CuO 43.19, 38.67; ZnO 0.42, 0.20; Al2O30.04, 4.68; Fe2O3 0.00, 0.36; P2O5 0.59, 0.78; V2O5 0.01, 0.04; As2O5 40.72, 43.01; SO3 0.35, 0.00; total 99.22, 99.84. The empirical formulae, based on 18 O a.p.f.u., are shchurovskyite: K2.05Rb0.01Ca0.96Cu5.92Zn0.06Al0.01P0.09S0.05As3.86O18;dmisokolovite: Na0.28K2.36Mg0.09Ca0.04Cu5.04Zn0.04 Al0.95Fe0.053+P0.11As3.88O18. The strongest reflections of X-ray powder patterns [d,Å(I)(hkl)]are shchurovskyite: 8.61(100)(200, 001), 5.400(32)(110), 2.974(32)(312, 510), 2.842(47)(003, 020), 2.757(63) (601, 511), 2.373(36)(512, 420) and 2.297(31)(421, 222, 313); dmisokolovite: 8.34(95)(002), 5.433(84)(110), 2.921(66)(510, 314), 2.853(58)(511, 020) and 2.733(100)(006, 512, 602). Shchurovskyiteis monoclinic, C2, a = 17.2856(9), b = 5.6705(4), c = 8.5734(6) Å, β = 92.953(6)°, V = 839.24(9) Å3 and Z = 2. Dmisokolovite is monoclinic, C2/c, a = 17.0848(12), b = 5.7188(4), c =16.5332(12) Å, β = 91.716(6)°, V = 1614.7(2) Å3 and Z = 4. Their crystal structures [single-crystal X-ray diffraction data, R = 0.0746 (shchurovskyite) and 0.1345 (dmisokolovite: model)] are closely related in the topology of the main buildingunits. They are based on a quasi-framework consisting of AsO4 tetrahedra and polyhedra centred by Cu in shchurovskyite or by Cu and Al in dmisokolovite. K and Ca are located in channels of the quasi-framework. The minerals are named in honour of outstanding Russian geologists andmineralogists Grigory Efimovich Shchurovsky (1803–1884) and Dmitry Ivanovich Sokolov (1788–1852).
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González-Moreno, F. I., R. V. Tolentino-Hernández e F. J. Espinosa-Faller. "Optical, structural and morphology study of Cu2O/Cu and GO/Cu2O/Cu films prepared by pulsed electrodeposition and electrophoresis." Journal of Physics: Conference Series 2699, n.º 1 (1 de fevereiro de 2024): 012017. http://dx.doi.org/10.1088/1742-6596/2699/1/012017.
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Abstract In this work, copper (I) oxide films were prepared by pulsed electrodeposition onto copper substrates. Graphene oxide was deposited on the Cu2O/Cu films by cathodic electrophoresis. The films were studied by X-ray diffraction, Raman spectroscopy, optical reflectance and atomic force microscopy. The bandgap of the Cu2O/Cu films is close to 1.8 eV due to the presence of defects and decreases to close to 1.1 eV with GO deposition due to the oxidation of Cu2O to CuO on the surface. When GO was deposited, a reduction in the mean height was observed, indicating coverage of the entire surface. A topographic transformation of the surface was also observed, consisting of an increase in grain size and homogenization of the grain shape after GO deposition, possibly due to phase transformation. This work is the first step to prepare fully wet deposited thin film ZnO/GO/Cu2O/Cu solar cells.
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Tofighi, Ghazal, Henning Lichtenberg, Abhijeet Gaur, Wu Wang, Stefan Wild, Karla Herrera Delgado, Stephan Pitter, Roland Dittmeyer, Jan-Dierk Grunwaldt e Dmitry E. Doronkin. "Continuous synthesis of Cu/ZnO/Al2O3 nanoparticles in a co-precipitation reaction using a silicon based microfluidic reactor". Reaction Chemistry & Engineering 7, n.º 3 (2022): 730–40. http://dx.doi.org/10.1039/d1re00499a.
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Mills, Stuart J., Uwe Kolitsch, Georges Favreau, William D. Birch, Valérie Galea-Clolus e Johannes Markus Henrich. "Gobelinite, the Co analogue of ktenasite from Cap Garonne, France, and Eisenzecher Zug, Germany". European Journal of Mineralogy 32, n.º 6 (25 de novembro de 2020): 637–44. http://dx.doi.org/10.5194/ejm-32-637-2020.
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Abstract. The new mineral gobelinite, ideally CoCu4(SO4)2(OH)6⚫6H2O, is a new member of the ktenasite group and the Co analogue of ktenasite, ZnCu4(SO4)2(OH)6⚫6H2O. It occurs at Cap Garonne (CG), Var, France (type locality), and Eisenzecher Zug (EZ), Siegerland, North Rhine-Westphalia, Germany (cotype locality). The mineral forms pale green, bluish green or greyish green, blocky to thin, lath-like crystals. They are transparent and non-fluorescent, with a vitreous, sometimes also pearly, lustre and a white streak having a pale-green cast. Mohs hardness is about 2.5. The crystals are brittle with an irregular fracture; no cleavage was observed. D(meas.) is 2.95(2) and D(calc.) is 2.907 g cm−3 (for empirical formula, CG). Common associates are brochantite and various other hydrated metal sulfates. Electron-microprobe analyses of the CG material yielded (wt. %) CuO 42.45, CoO 6.58, NiO 3.37, ZnO 3.14, SO3 22.12, and H2O 22.62 (calculated on structural grounds), and total = 100.30 wt. %, giving the empirical formula (based on 20 O atoms) (Co0.63Ni0.32Zn0.28Cu3.83)Σ5.06S1.98O20H18.00. The simplified formula is (Co,Ni)(Cu,Zn)4(SO4)2(OH)6⚫6H2O, and the endmember formula is CoCu4(SO4)2(OH)6⚫6H2O. Scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDS) analyses of the (Zn-free) EZ material gave the simplified average formula (Co0.92Ni0.21Mg0.01Cu3.79)Σ4.93(SO4)2.08(OH)6⚫6H2O. Optically, gobelinite (CG) is biaxial negative, with α=1.576(2), β=1.617(2) and γ=1.630(2); 2Vmeas=58(4)∘ and 2Vcalc=57.5∘. Dispersion is weak, r>v; orientation is X=β, Y=γ and Z≈α, with strong pleochroism X equaling colourless, Y equaling green and Z equaling pale green. The mineral is monoclinic, space group P21∕c, with a=5.599(1), b=6.084(1), c=23.676(5) Å, β=95.22(3)∘ and V=803.2(3) Å3 (at 100 K; CG) and a=5.611(1), b=6.103(1), c=23.808(5) Å, β=95.18(3)∘ and V=811.9(3) Å3 (at 298 K; EZ), respectively (Z=2). The eight strongest measured powder X-ray diffraction lines (d in Å (I) hkl (CG material)) are 11.870 (100) 002, 5.924 (40) 004, 4.883 (10) 102, 4.825 (15) 013, 3.946 (15) 006, 2.956 (15) 008, 2.663 (20) 202 and 2.561 (15) 1‾23. Single-crystal structure determinations gave R1=0.0310 (CG) and 0.0280 (EZ). The atomic arrangement is based on brucite-like sheets formed from edge-sharing, Jahn–Teller-distorted (4+2 coordination) CuO6 octahedra. These sheets are decorated on both sides with SO4 tetrahedra and linked via hydrogen bonds to interstitial, fairly regular Co(H2O)6 octahedra. The name alludes to the Old French word gobelin, equivalent to the German word kobold, from which the designation of the element cobalt was derived.
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Mohd Zabidi, Noor Asmawati, Tuan Syahylah Tuan Sulong e Sardar Ali. "Synthesis and Characterization of Cu/ZnO Catalyst on Carbon Nanotubes and Al2O3 Supports". Materials Science Forum 916 (março de 2018): 139–43. http://dx.doi.org/10.4028/www.scientific.net/msf.916.139.
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CO2 conversion into valuable chemicals is an attractive option to deal with the increasing CO2 concentration in the atmosphere. In this study, Cu/ZnO catalyst was synthesized on multi-walled carbon nanotubes (MWCNTs) and Al2O3 supports via incipient wetness impregnation method. The physicochemical properties of the catalysts were investigated using TEM, XRD, N2 adsorption-desorption analysis, H2-TPR and XPS. The performance of the synthesized catalysts in a CO2 hydrogenation reaction was evaluated in a fixed-bed reactor at 503 K, 22.5 bar and H2:CO2 ratio of 3:1. TEM images showed that Cu/ZnO nanoparticles were deposited inside the CNTs as well as on the exterior walls of the CNTs. The average CuO crystallite size on Al2O3 and CNTs supports was 15.7 and 11 nm, repectively. Results of H2-TPR studies showed that the reducibility of the catalyst was improved on the CNTs support. XPS analysis confirmed the presence of Cu2+ in the samples, however, the binding energy of Cu 2p3/2 peak on the Al2O3 support was shifted to higher value compared to that of CNTs support. Products obtained from the CO2 hydrogenation reaction in the presence of these catalyts were methanol, ethanol, methyl formate and methane. The CO2 conversion of around 23% was obtained using both types of catalysts, however, Cu/ZnO on CNTs resulted in higher yield of methyl formate compared to that of Al2O3-supported catalyst.
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Li, Pen-Xin, Ai-Yun Yang, Lang Xin, Biao Xue e Chun-Hao Yin. "Photocatalytic Activity and Mechanism of Cu2+ Doped ZnO Nanomaterials". Science of Advanced Materials 14, n.º 10 (1 de outubro de 2022): 1599–604. http://dx.doi.org/10.1166/sam.2022.4363.
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The photocatalytic activity and mechanism of photocatalysts made of ZnO nanoparticles before and after doping with different Cu2+ concentrations were studied by electron paramagnetic resonance and X-ray diffraction. The nanoparticles were prepared using sol–gel method. UV-vis spectrometers characterized the photocatalytic degradation effect of the composite samples on methyl orange solution. The results of X-ray diffraction showed that the hexagonal wurtzite structure of ZnO changed little by Cu2+ doping. With the increase in doping concentration, the CuO and Cu2O diffraction peaks were detected successively in the crystal. The results of the electron paramagnetic resonance test for all samples indicated three kinds of unpaired electrons with g factors of 2.07, 1.997, and 1.954. Further analysis confirmed them to be Cu2+, V+O, and Zn–H complexes. Photocatalytic degradation results of methyl orange showed that proper doping (c(Cu2+) = 2%) could improve the photocatalytic activity of ZnO. The main reason for the increase was that the substitution of Cu2+ for Zn2+ in the crystal lattice produced Zni, and the Zn atom could act as the donor to release electrons, so that the number of electrons in the material increased, which indirectly increased the superoxide radical content in the solution and improves the photocatalytic activity of ZnO.
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Vusikhis, Alexander S., Evgeny N. Selivanov, Stanislav N. Tyushnyakov e Viktor P. Chentsov. "Metal reduction by hydrogen from the B2O3-СaO-Ni(Zn, Pb, Cu)O melts thermodynamic modeling". Butlerov Communications 61, n.º 2 (29 de fevereiro de 2020): 145–51. http://dx.doi.org/10.37952/roi-jbc-01/20-61-2-145.
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Thermodynamic modeling is used to describe the metal reduction processes by hydrogen from oxide melt in the B2O3-CaO- MeO (Me – Ni, Zn, Pb, Cu) system. Open systems approximation with periodic removal of metal particles and gases from the working melt composition is used in the method. By this work we present the thermodynamic modeling results of metal reduction processes (Ni, Cu, Pb, Zn) by Hydrogen. The reducible metals oxides content in the all melts was 3 mass %, and the mass ratio of B2O3/CaO was taken as 3 to be close to eutectic composition. The calculations made it possible to determine such parameters as oxide melt compositions and elements reduction degree depending on the induced gas quantity. of the Nickel, Copper, Lead and Zinc reduction process simulation from B2O3-CaO-MeO melts proved the reduction process by Hydrogen is similar to that which was earlier established when Carbon monoxide was used as the reducing agent. When Copper is reduced from CuO, the process occurs with intermediate Cu2O oxide formation (CuO → Cu2O → Cu). The Nickel (NiO → Ni), Lead (PbO → Pbs + Pbg) and Zinc (ZnO → Zng) recovery have been realized by one stage. The non-ferrous metals change content in the oxide melt and the degrees of its reduction depending on temperature and reducing agent quantity introduced are described by the second-order polynomial functional equations. Comparison of the Carbon monoxide and Hydrogen used for Nickel, Copper, Lead, and Zinc reducing to 90% metallization degree proved much less Hydrogen consumption.
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Vusikhis, Alexander S., Evgeny N. Selivanov, Stanislav N. Tyushnyakov e Victor P. Chentsov. "Thermodynamic modeling of reduction of metals from B2O3-CaO-Ni(Zn,Pb,Cu)O melts carbon monoxide". Butlerov Communications 59, n.º 9 (30 de setembro de 2019): 125–31. http://dx.doi.org/10.37952/roi-jbc-01/19-59-9-125.
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Thermodynamic modeling technique is used to describe the metal reduction from oxide melt by carbon monoxide. The B2O3-CaO-MeO (Me – Ni, Zn, Pb, Cu) system, was used with periodic output of the metal phase and gases from the working body. The approach originality is that the equilibrium is determined for each single portion of the gas injected into the working body, and the metal oxides content being reduced in each calculation cycle is taken from the previous data. This approach gives qualitative possibility to make simulated processes closer to real ones. The proposed method calculations allow determining, such parameters as the oxide melt and metal phase compositions, degree of elements reduction, oxide and metal phases mass ratio, equilibrium composition of the gas, reducing ability of gas utilization degree, and others, depending on the introduced gas quantities. Reducing process modeling of Nickel, Copper, Lead and Zinc from B2O3-CaO-MeO melts gives opportunity to determine the process for each metal. Copper reducing from CuO, goes with intermediate oxide (CuO → Cu2O → Cu) formation. Reduction of Nickel (NiO → Ni), Lead (PbO → Pbs + Pbg) and Zinc (ZnO → Zng) proceeds in one stage. The temperature dependence of the non-ferrous metals content in the oxide melt, its reduction degree and reducing agent quantity introduced are described by the second-order polynomial equations. The information obtained may be useful for thermo-extraction processes prognosis during the Nickel, Copper, Lead, and Zinc extraction from non-ferrous metallurgy slag in bubbling process of oxide melt by reducing gases.
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Mikkelsen, J. C., J. B. Boyce e F. Bridges. "XAFS Characterization of Cu-Doped ZnO Films". MRS Proceedings 307 (1993). http://dx.doi.org/10.1557/proc-307-173.
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ABSTRACTThis paper describes x-ray absorption measurements made on 10 to 16-μm-thick films of ZnO, which contained 5 mol% CuO, and were grown by reactive sputtering. We compare our experimental near-edge and XAFS results to models for Cu-O phases and Cu incorporation into the ZnO lattice, and we conclude that roughly half of the Cu atoms are substitutional for Zn on the wurtzite lattice and the other half is in a highly disordered phase, which has an XAFS signature which is similar to disordered CuO. Our results are compared to other structural studies of Cu-doped ZnO materials.
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Patel, Monika, Sunita Mishra, Ruchi Verma e Deep Shikha. "Synthesis of ZnO and CuO nanoparticles via Sol gel method and its characterization by using various technique". Discover Materials 2, n.º 1 (29 de março de 2022). http://dx.doi.org/10.1007/s43939-022-00022-6.
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AbstractNanotechnology is a completely unique branch of technology that offers with substances in a very small size between (1–100 nm) with various crystal shapes. Metals have ability to produce large number of oxides. These metal oxides play a major role in many areas of chemistry, physics, material science and food science. In this research, Zinc Oxide (ZnO) and Copper (II) oxide nanoparticles were synthesized via sol–gel process using zinc nitrate and copper (II) nitrate as precursor respectively. The characterization of CuO and ZnO nanoparticles was done by using various techniques. X-ray Diffraction (XRD) indicates the crystallinity and crystal size of CuO and ZnO nanoparticle. Fourier transform infrared spectroscopy (FT-IR) was used to get the infrared spectrum of the sample indicating composition of the sample which contains various functional groups. XRD result shows the particle size of CuO at highest peak 29.40140 was 61.25 nm and the particle size of ZnO at highest peak 36.2476° was 21.82 nm. FT-IR spectra peak at 594.56 cm-1 indicated characteristic absorption bands of ZnO nanoparticles and the broad band peak at 3506.9 cm−1 can be attributed to the characteristic absorption of O–H group. The analysis of FT-IR spectrum of CuO shows peaks at 602.09, 678.39, and 730.19 cm−1 which refer to the formation of CuO. SEMimages indicate the morphology of CuO and ZnO nanoparticles. Result of EDX characterization indicates that the both synthesized nanoparticles have good purity with very less amount of impurities. EDX data indicates that Cu content was 54.56%, oxygen content was 33.75% in CuO nanoparticles and Zn determined by EDX was 40.77 and O was 45.82 in ZnO. Graphical Abstract
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El-Sawaf, Ayman K., Shahira H. El-Moslamy, Elbadawy A. Kamoun e Kaizar Hossain. "Green synthesis of trimetallic CuO/Ag/ZnO nanocomposite using Ziziphus spina-christi plant extract: characterization, statistically experimental designs, and antimicrobial assessment". Scientific Reports 14, n.º 1 (24 de agosto de 2024). http://dx.doi.org/10.1038/s41598-024-67579-5.
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AbstractIn this study, Ziziphus spina christi leaves was used to synthesize a trimetallic CuO/Ag/ZnO nanocomposite by a simple and green method. Many characterizations e.g. FTIR, UV–vis DRS, SEM–EDX, TEM, XRD, zeta-size analysis, and DLS, were used to confirm green-synthesized trimetallic CuO/Ag/ZnO nanocomposite. The green, synthesized trimetallic CuO/Ag/ZnO nanocomposite exhibited a spherical dot-like structure, with an average particle size of around 7.11 ± 0.67 nm and a zeta potential of 21.5 mV. An extremely homogeneous distribution of signals, including O (79.25%), Cu (13.78%), Zn (4.42%), and Ag (2.55%), is evident on the surface of green-synthetic nanocomposite, according to EDX data. To the best of our knowledge, this is the first study to effectively use an industrially produced green trimetallic CuO/Ag/ZnO nanocomposite as a potent antimicrobial agent by employing different statistically experimental designs. The highest yield of green synthetic trimetallic CuO/Ag/ZnO nanocomposite was (1.65 mg/mL), which was enhanced by 1.85 and 5.7 times; respectively, by using the Taguchi approach in comparison to the Plackett–Burman strategy and basal condition. A variety of assays techniques were utilized to evaluate the antimicrobial capabilities of the green-synthesized trimetallic CuO/Ag/ZnO nanocomposite at a 200 µg/mL concentration against multidrug-resistant human pathogens. After a 36-h period, the tested 200 µg/mL of the green-synthetic trimetallic CuO/Ag/ZnO nanocomposite effectively reduced the planktonic viable counts of the studied bacteria, Escherichia coli and Staphylococcus aureus, which showed the highest percentage of biofilm reduction (98.06 ± 0.93 and 97.47 ± 0.65%; respectively).
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Esbergenova, Amugul, Mirabbos Hojamberdiev, Shavkat Mamatkulov, Rivojiddin Jalolov, Debin Kong, Olim Ruzimuradov e Ulugbek Shaislamov. "Correlating Cu dopant concentration, optoelectronic properties, and photocatalytic activity of ZnO nanostructures: experimental and theoretical insights". Nanotechnology, 29 de agosto de 2024. http://dx.doi.org/10.1088/1361-6528/ad750b.
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Abstract The photocatalytic activity of photocatalysts can be enhanced by cation doping, and the dopant concentration plays a key role in achieving high efficiency. This study explores the impact of copper (Cu) doping at concentrations ranging from 0% to 10% on the microstructural, optical, electronic, and photocatalytic properties of zinc oxide (ZnO) nanostructures. The X-ray diffraction analysis shows a non-linear alteration in the lattice parameters with increasing the Cu content and the formation of CuO as a secondary phase at the Cu concentration of >3%. Density functional theory (DFT) calculations provide insights into the change in the electronic structures of ZnO induced by Cu doping, leading to the formation of localized d electronic levels above the valence band maximum. The modulation of the electronic structure of ZnO by Cu doping facilitates the visible light absorption via O 2p → Cu 3d and Cu 3d → Zn 2p transitions. Photoluminescence spectroscopy reveals a quenching of the defect-related emission peak at approximately 570 nm for all Cu-doped ZnO nanostructures, indicating a reduction in the structural and other defects. The photocatalytic activity tests confirm that the ZnO nanostructures doped with 3% Cu exhibit the highest efficiency compared to other samples due to the suitable band-edge position and visible light absorption.
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Taha, Walaa M., Mohamed Morsy, Nadra A. Nada e Medhat A. Ibrahim. "Modeling the electronic properties for CNT interacted with ZnO, CuO, and Co3O4". Optical and Quantum Electronics 54, n.º 9 (3 de agosto de 2022). http://dx.doi.org/10.1007/s11082-022-03974-4.
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AbstractBecause of the wide applications of carbon nanotubes (CNTs) and magic properties of metal oxides, Hartree–Fock quantum mechanical calculations at HF/STO-3G were applied to study the electronic properties of CNTs and their interaction with ZnO, CuO, and Co3O4. Calculations were conducted to calculate HOMO/LUMO bandgap energy ∆E, molecular electrostatic potential (MESP), and total dipole moment (TDM) for CNTs, CNT-Zn-O, CNT-Cu-O, CNT-Co-O, and CNT-O-Zn, CNT-O-Cu, CNT-O-Co following the two mechanisms of interaction as adsorbed and complex state. The calculations show that the interaction of CNTs with metal oxides increases its reactivity where MESP indicated to more distribution charges and an increase in the TDM value after the interaction of CNTs with metal oxides. Where the interaction of CNT-Co-O as adsorbed state has the highest TDM with the lowest bandgap ∆E which confirms that CNT-Co3O4 can be used in sensing devices.
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Davies, Geoffrey, Bill C. Giessen e Hui-Li Shao. "Mixed Metal Oxide Synthesis by Thermolyses of Simple Heteropolymetallic Precursors in Oxygen". MRS Proceedings 249 (1991). http://dx.doi.org/10.1557/proc-249-87.
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ABSTRACTStepwise transmetalation of the neutral molecular target (µ4-O)N4 Cu4 C16(N is a monodentate pyridine) with M(NS)n transmealators (NS is a monanionic S-methyl hydrazinecarbodithioate ligand, M is Co (n = 2 or 3), Ni or Zn (n = 2)) in aprotic solvents gives a large family of heteropolymetallic products (µ4 - O)N4 (Co,Ni,Cu,Zn)4 C16 that contain from one to four different metals. Thermolysis of these solid products in flowing O2 at 220 - 250°C gives uniform, highly dispersed mixtures of the respective metal oxides. For example, thermolysis of bulk precursor (µ4 -O)N4 CoNiCuZnCl6 gives a uniform mixture of 1 - 2° particles of Co3 O4, NiO, CuO and ZnO.
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Zhu, Wenli, Juan Du e Qiaoling Yang. "Construction of a Double Z‐Scheme CuO/Cu2O/CuS/ZnO Quaternary Heterojunction Photocatalyst with Enhanced Solar‐Driven Photocatalytic Performance for Sulfamethoxazole Degradation". ChemistrySelect 9, n.º 30 (6 de agosto de 2024). http://dx.doi.org/10.1002/slct.202400261.
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AbstractA novel CuO/Cu2O/CuS/ZnO quaternary heterojunction photocatalyst was constructed through a facile microwave technique. The structure, morphology and optical properties were characterized and explored. The photocatalytic activity of CuO/Cu2O/CuS/ZnO quaternary composite was assessed by antibiotic sulfamethoxazole under the simulated solar light irradiation. The quaternary composite manifested more excellent photocatalytic performance than the pristine ZnS and CuO/Cu2O. Moreover, the effects of ascorbic acid concentration on removal efficiency of sulfamethoxazole were discussed, revealing the importance of Cu2O in sulfamethoxazole removal. Particularly, as the ascorbic acid was 0.50 M, the total removal efficiency of sulfamethoxazole at an initial concentration of 20 mg/L was approximately 99.17 %, and the fitted pseudo‐first‐order kinetic rate constant reached 0.0380/min, which were 1.73 and 6.91 times of that in the absence of ascorbic acid, respectively. A double Z‐scheme charge transfer mechanism was confirmed by the reactive species trapping tests, which demonstrated that superoxide radicals and holes were the major reactive species responsible for sulfamethoxazol degradation. CuO/Cu2O/CuS/ZnO nanocomposite provided an interesting perspective for a highly efficient quaternary photocatalyst that could be employed for remediation antibiotics.
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Yoon, Bola, João V. Campos, Isabela R. Lavagnini, Viviana Avila, James M. Gardner, Sanjit K. Ghose e Lílian M. Jesus. "Phase evolution during conventional and reactive flash sintering of (Mg,Ni,Co,Cu,Zn)O via in situ X‐ray diffraction". Journal of the American Ceramic Society, 24 de outubro de 2023. http://dx.doi.org/10.1111/jace.19503.
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AbstractReactive flash sintering (RFS) enables the simultaneous synthesis and sintering of ceramics and has been shown to affect the reaction pathway of different materials. Herein, in situ synchrotron X‐ray diffraction (XRD) is used to investigate the (Mg,Ni,Co,Cu,Zn)O entropy‐stabilized oxide formation during: (i) conventional heating and (ii) RFS under current rate‐controlled mode. The same reaction pathway is verified in both instances: the starting rock‐salt (RS), spinel (Co3O4), tenorite (CuO), and wurtzite (ZnO) phases transform into a single RS phase with a (1 1 1) to (2 0 0) intensity ratio of 0.67, consistent with a random distribution of the cations into the structure. Pt lattice peak shift from the XRD patterns is used as standard to monitor the sample surface temperature, revealing a strong endothermic reaction during the RS single‐phase formation (Pt peaks shift toward higher angles while increasing sample temperature/current density). In RFS, the single‐phase RS structure is formed in just 60 s at a furnace temperature of 600°C and a current rate of 220 mA mm−2/min. Therefore, RFS greatly accelerates the synthesis of (Mg,Ni,Co,Cu,Zn)O, however, it does not play a role in the reaction pathway for this material formation.