Статті в журналах: "Nanocomposites - Mesoporous Structure"

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Gudiño-Rivera, Javier, Francisco J. Medellín-Rodríguez, Carlos Ávila-Orta, Alma G. Palestino-Escobedo, and Saúl Sánchez-Valdés. "Structure/Property Relationships of Poly(L-lactic Acid)/Mesoporous Silica Nanocomposites." Journal of Polymers 2013 (December 24, 2013): 1–10. http://dx.doi.org/10.1155/2013/162603.

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Biodegradable poly(L-lactic acid) (PLLA)/mesoporous silica nanocomposites were prepared by grafting L-lactic acid oligomer onto silanol groups at the surface of mesoporous silica (SBA-15). The infrared results showed that the lactic acid oligomer was grafted onto the mesoporous silica. Surface characterization of mesoporous silica proved that the grafted oligomer blocked the entry of nitrogen into the mesopores. Thermal analysis measurements showed evidence that, once mixed with PLLA, SBA-15 not only nucleated the PLLA but also increased the total amount of crystallinity. Neat PLLA and its nanocomposites crystallized in the same crystal habit and, as expected, PLLA had a defined periodicity compared with the nanocomposites. This was because the grafted macromolecules on silica tended to cover the lamellar crystalline order. The g-SBA-15 nanoparticles improved the tensile moduli, increasing also the tensile strength of the resultant nanocomposites. Overall, the silica concentration tended to form a brittle material.

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2

Fu, Xin. "The High Stability Mesoporous MgO-ZrO₂Materials as CO₂ Adsorbents." Advanced Materials Research 490-495 (March 2012): 3797–801. http://dx.doi.org/10.4028/www.scientific.net/amr.490-495.3797.

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A novel CO2 absorbent, MgO-ZrO2 nanocomposite was synthesized via appropriate sol-gel process. The structure and surface properties of the as-prepared materials were characterized by XRD, N2 adsorption-desorption and CO2-TPD techniques. It was found the as-prepared materials showed high thermal stability, and their mesoporous framework was well preserved even after calcinations at 700oC. In addition, the nanocomposites exhibited appropriate basic strength and the basic sites were tightly anchored to the substrate, which greatly improved the stability of the surface basicity. Owing to the advantages of the mesoporous structure and the surface basicity, the as-prepared MgO-ZrO2 nanocomposites showed high CO2 adsorption capacity. Moreover, the high thermal stability of MgO-ZrO2 could greatly increase their performance in high-temperature application, which remarkably overcame the poor thermal stability of those organic group grafted porous silicas.

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Salimian, S., A. Zadhoush, and A. Mohammadi. "A review on new mesostructured composite materials: Part I. synthesis of polymer-mesoporous silica nanocomposite." Journal of Reinforced Plastics and Composites 37, no. 7 (January 10, 2018): 441–59. http://dx.doi.org/10.1177/0731684417752081.

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Mesoporous silicas are inorganic materials with large surface areas, uniform framework structures and readily controlled pore diameters which are synthesized in the presence of surfactants as structure-directing agents, followed by the removal of the surfactant by extraction or calcination. Due to their characteristics, such as ordered structure, high surface area, and favorable interfacial interactions between silica surface and the polymer, they have found excellent potential application for use as reinforcing agents for several engineering polymer systems. While a large number of different synthesis approaches for the preparation of mesoporous silica-polymer nanocomposites has been reported in literature, there is nevertheless a growing need for verified synthesis methods of mesoporous silica-polymer materials. This paper presents a review of the literature on the methods for synthesizing polymer-mesoporous silica nanocomposites and discusses some unique properties of these composites.

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4

Karimi, Loghman. "Combination of mesoporous titanium dioxide with MoS2 nanosheets for high photocatalytic activity." Polish Journal of Chemical Technology 19, no. 2 (June 1, 2017): 56–60. http://dx.doi.org/10.1515/pjct-2017-0028.

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Abstract This study presents a facile approach for the preparation of MoS2 nanosheet decorated by porous titanium dioxide with effective photocatalytic activity. Mesoporous titanium dioxide nanostructures first synthesized by a hydrothermal process using titanium (III) chloride and then the MoS2/TiO2 were prepared through mixing of MoS2 nanosheet with mesoporous titanium dioxide under ultrasonic irradiation. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), and Brunauer-Emmett-Teller (BET) analysis. The results showed that the nanocomposite has mesoporous structure with specific surface area of 176.4 m2/g and pore diameter of 20 nm. The as-prepared MoS2/TiO2 nanocomposites exhibited outstanding photocatalytic activity for dye degradation under sunlight irradiation, which could be attributed to synergistic effect between the molybdenum disulfide nanosheet and mesoporous titanium dioxide. The photocatalytic performance achieved is about 2.2 times higher than that of mesoporous TiO2 alone. It is believed that the extended light absorption ability and the large specific surface area of the 2D MoS2 nanosheets in the nanocomposite, leading to the enhanced photocatalytic degradation activity.

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Khorasani, Mahsa, and Hossein Naeimi. "Fabrication and characterization of mesoporous yolk–shell nanocomposites as an effective reusable heterogeneous base catalyst for the synthesis of ortho-aminocarbonitrile tetrahydronaphthalenes." RSC Advances 13, no. 27 (2023): 18690–99. http://dx.doi.org/10.1039/d3ra02740f.

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Mesoporous yolk–shell nanocomposites were loaded with a mobile CaMg core inside the silica shell. Also, these prepared inside the inner cavity of a novel structure that consists of hollow mesoporous silica spheres.

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Chen, X. J., J. C. Xu, H. X. Jin, D. F. Jin, B. Hong, H. L. Ge, and X. Q. Wang. "Preparation and Characterization of Magnetic Cobalt Ferrites/SBA-15 Nanocomposite Adsorbents and the Removal of Methylene Blue." Nano 12, no. 05 (March 28, 2017): 1750060. http://dx.doi.org/10.1142/s1793292017500606.

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In this paper, ordered mesoporous SBA-15 silica was synthesized by the hydrothermal method, and then a series of CoFe2O4/SBA-15 nanocomposites were synthesized by a facile impregnation method. X-ray diffraction and N2 adsorption–desorption isotherms were used to characterize the microstructure and morphology of SBA-15 and CoFe2O4/SBA-15 nanocomposites. CoFe2O4 nanoparticles presented spinel phase structure and existed in the mesopores of SBA-15. The magnetic response of CoFe2O4/SBA-15 nanocomposites was characterized with vibrating sample magnetometer (VSM). The adsorption efficiency of CoFe2O4/SBA-15 nanocomposites for methylene blue increased firstly with the increasing CoFe2O4 content, and then decreased. Sample-2 (SBA-15: CoFe2O[Formula: see text]: 0.1 in the precursor) not only presented the best adsorptive performance, but also could be separated and retrieved effectively by magnetic separation technique.

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Jalani, Mohamad Azani, Leny Yuliati, Siew Ling Lee, and Hendrik Oktendy Lintang. "Highly ordered mesoporous silica film nanocomposites containing gold nanoparticles for the catalytic reduction of 4-nitrophenol." Beilstein Journal of Nanotechnology 10 (July 5, 2019): 1368–79. http://dx.doi.org/10.3762/bjnano.10.135.

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We report that transparent mesostructured silica/gold nanocomposite materials with an interpore distance of 4.1 nm, as-synthesized from a templated sol–gel synthesis method using discotic trinuclear gold(I) pyrazolate complex, were successfully utilized for the fabrication of thin film mesoporous silica nanocomposites containing gold nanoparticles. The material exhibited a highly ordered hexagonal structure when subjected to a thermal hydrogen reduction treatment at 210 °C. In contrast, when the material was subjected to calcination as a heat treatment from 190 to 450 °C, the thin film nanocomposites showed an intense d 100 X-ray diffraction peak. Moreover, gold nanoparticles inside the thin film nanocomposites were confirmed by the presence of the d 111 diffraction peak at 2θ = 38.2°, a surface plasmon resonance peak between 500–580 nm, and the spherical shape observed in the transmission electron microscope images, as well as the visual change in color from pink to purple. Interestingly, by simply dipping the material into a reaction solution of 4-nitrophenol at room temperature, the highly ordered structure of the as-fabricated silica/gold nanoparticle thin film composite after thermal hydrogen reduction at 210 °C resulted in an improved catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol compared to the material calcined at 250 °C. Such catalytic activity is due to the presence of gold nanoparticles of smaller size in the silicate channels of the highly ordered mesoporous film nanocomposites.

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Al-Khthami, Nada D., Mohammed Alsawat, Reda M. Mohamed, Yousef G. Alghamdi, and Zaki I. Zaki. "Extremely Effective Visible Light-Driven Generation of Hydrogen by Sol–Gel LaFeO3-Decorated g-C3N4 Photocatalyst." Nanoscience and Nanotechnology Letters 12, no. 11 (November 1, 2020): 1255–64. http://dx.doi.org/10.1166/nnl.2020.3241.

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In order to create a new design for an efficient photocatalyst, you need to decrease the obtained band gap and isolate the charge carriers photogenerated while setting up a new visible light methodology. The latter option could be accomplished via combination of catalyst in the metal oxide form over the surface of semiconductor. Hence, the current work aimed at synthesizing a new nanocomposite material from LaFeO3/g-C3N4 through the use of mesoporous silica as a template processing g-C3N4 higher surface area, which was subsequently decorated with LaFeO3. The LaFeO3 of variable content of 1∼4% was used to decorate our targeted basic material. The structure was confirmed by ordinary techniques, in addition to photocatalytic ability via splitting water reaction. g-C3N4 and LaFeO3 photocatalytic efficiencies were compared to the newly developed LaFeO3/g-C3N4 nanocomposites showing their outstanding activity. The optimum LaFeO3 content was confirmed as 3%, which gave higher photocatalytic efficiency against both g-C3N4 and LaFeO3 (34 and 21 times respectively). To enhance the catalytic system efficiency, a scavenger with a positive hole was added as glycerol. A maximum of five runs of higher efficient reuse was examined as required, as well as stable nanocomposite photocatalyst. The mesoporous structure, high surface area, and capacity of charge separation over the photocatalysis process were all investigated as main conditions which affect photocatalytic activity of LaFeO3/g-C3N4 nanocomposites.

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Jubgang Fandio, Défi Junior, Stéphanie Sauze, Abderraouf Boucherif, Richard Arès, and Denis Morris. "Structural, optical and terahertz properties of graphene-mesoporous silicon nanocomposites." Nanoscale Advances 2, no. 1 (2020): 340–46. http://dx.doi.org/10.1039/c9na00502a.

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Ladavos, Athanasios, Aris E. Giannakas, Panagiotis Xidas, Dimitrios J. Giliopoulos, Maria Baikousi, Dimitrios Gournis, Michael A. Karakassides, and Konstantinos S. Triantafyllidis. "Preparation and Characterization of Polystyrene Hybrid Composites Reinforced with 2D and 3D Inorganic Fillers." Micro 1, no. 1 (May 7, 2021): 3–14. http://dx.doi.org/10.3390/micro1010002.

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Polystyrene (PS)/silicate composites were prepared with the addition of two organoclays (orgMMT and orgZenith) and two mesoporous silicas (SBA-15 and MCF) via (i) solution casting and (ii) melt compounding methods. X-ray diffraction (XRD) analysis evidenced an intercalated structure for PS/organoclay nanocomposites. Thermogravimetric analysis indicated improvement in the thermal stability of PS-nanocomposites compared to the pristine polymer. This enhancement was more prevalent for the nanocomposites prepared with a lab-made organoclay (orgZenith). Tensile measurement results indicated that elastic modulus increment was more prevalent (up to 50%) for microcomposites prepared using mesoporous silicas as filler. Organoclay addition led to a decrease in oxygen transmission rate (OTR) values. This decrement reached up to 50% for high organoclay content films in comparison to pristine PS film. Decrement above 80% was measured for microcomposites with mesoporous silicas and 5 wt% filler content obtained via melt compounding.

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Albadri, Abuzar E. A. E., Mohamed Ali Ben Aissa, Abueliz Modwi, and Sayed M. Saleh. "Synthesis of Mesoporous Ru-ZnO@g-C3N4 Nanoparticles and Their Photocatalytic Activity for Methylene Blue Degradation." Water 15, no. 3 (January 25, 2023): 481. http://dx.doi.org/10.3390/w15030481.

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Cleaning contaminated water under light with a novel type of heterogeneous photocatalysts is regarded as a critical method for wastewater resolution. Thus, a unique mesoporous Ru-ZnO@g-C3N4 nanocomposite with an increased surface area was synthesized through the ultrasonic technique in the presence of methanol. The X-ray diffraction pattern efficiently validated the crystal structure of the Ru-ZnO hybrid and allowed it to be integrated into the g-C3N4 structure. TEM imaging revealed the Ru-ZnO nanocomposite as spherical particles spread uniformly throughout the g-C3N4 nanosheet. X-ray photoelectron spectroscopy (XPS) was applied to determine the bonding properties of the samples. Under visible illumination, the synthesized nanocomposites of Ru-ZnO@g-C3N4 were evaluated as a new effective photocatalyst for degrading organic pigments in aquatic conditions.

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Li, Huan-Huan, Jia-Wei Wang, Xing-Long Wu, Hai-Zhu Sun, Feng-Mei Yang, Kang Wang, Lin-Lin Zhang, Chao-Ying Fan, and Jing-Ping Zhang. "A novel approach to prepare Si/C nanocomposites with yolk–shell structures for lithium ion batteries." RSC Adv. 4, no. 68 (2014): 36218–25. http://dx.doi.org/10.1039/c4ra07043g.

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A novel method was developed to prepare mesoporous Si/C nanocomposites with yolk–shell structure (MSi@C), which showed good retention of specific capacity (1264.7 mA h g⁻¹ after 150 cycles with coulombic efficiency above 99%). This work provides an alternative method to fabricate yolk–shell structured materials.

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Seroglazova, Anna S., Maria I. Chebanenko, and Vadim I. Popkov. "Synthesis, structure, and photo-Fenton activity of PrFeO3-TiO2 mesoporous nanocomposites." Kondensirovannye sredy i mezhfaznye granitsy = Condensed Matter and Interphases 23, no. 4 (November 24, 2021): 548–60. http://dx.doi.org/10.17308/kcmf.2021.23/3674.

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Porous nanocomposites based on PrFeO3-TiO2 were synthesized using the glycine-nitrate combustion method with different values of mass content of TiO2 (0–7.5 %) and subsequent heat treatment in air. The results of X-ray phase analysis and Raman spectroscopy confirmed the presence of ultradispersed TiO2, structurally close to that of anatase. The morphology, specific surface area, and porous structure of the obtained powders were characterized by scanning electron microscopy and adsorption-structural analysis, the results of which showed that the samples had a foam-like mesoporous structure.The specific surface area and the average pore size were in the ranges of 7.6–17.8 m2/g and 7.2–15.2 nm, respectively, and varied depending on the TiO2 content. The optical properties of the nanocomposites were studied by UV-visible diffuse reflection spectroscopy, the energy of the band gap was calculated as 2.11–2.26 eV. The photocatalytic activity of PrFeO3‑TiO2 nanocomposites was investigated in the process of photo-Fenton-like degradation of methyl violet under the action of visible light. It was shown that the maximum reaction rate constant was 0.095 min-1, which is ten times higher than the value for the known orthoferrite-based analogs. The obtained photocatalysts were also characterized by their high cyclic stability. Based on the studies carried out, the obtained porous PrFeO3-TiO2 nanocomposites can be considered to be apromising basis for photocatalysts applied in advanced oxidative processes of aqueous media purification from organic pollutants.

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14

Yu, Qian, Jing Jing Sang, Ai Ping Fu, and Hong Liang Li. "Synthesis and Characterization of Magnetic Nanocomposite Fe₃O₄@nSiO₂@mSiO₂with Dual Shells Containing Non-Porous Silica and Mesoporous Silica Structure." Advanced Materials Research 926-930 (May 2014): 308–11. http://dx.doi.org/10.4028/www.scientific.net/amr.926-930.308.

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Magnetic nanocomposites of Fe3O4@nSiO2@mSiO2 were synthesized by a two-step template method. Firstly, Fe3O4 magnetic core encapsulated clusters of SiO2 nanoparticles (Fe3O4@nSiO2, non-porous SiO2) was prepared by a spray drying method. Then the core-shell spheres of Fe3O4@nSiO2 were coated further with an m-SiO2 layer (mesoporous silica) by a sol-gel process using CTAB as a template. The resultant samples were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Nitrogen adsorption-desorption and Magnetic measurements. The acquired magnetic nanocomposites possess abundant mesopores, thus extends their potential application in biomedical and wastewater treatment due to their magnetic separation ability upon an external magnetic field.

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Bakina, O. V., S. O. Kazantsev, A. V. Pervikov, E. A. Glazkova, N. V. Svarovskaya, A. S. Lozhkomoev, and E. G. Khorobraya. "Structure, morphology and antibacterial properties of mesoporous nanocomposites AlOOH-metal." Physics and Chemistry of Materials Treatment 4 (2020): 31–40. http://dx.doi.org/10.30791/0015-3214-2020-4-31-40.

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The risk of development of resistance in Staphylococcus aureus to the antibiotics and antiseptics leads to the search of new efficient antibacterial agents for biomedical applications. In present work, bimetallic Al-Cu, Al-Ag nanoparticles were synthesized by the electrical explosion of wires in argon atmosphere. The mass ratio of aluminum and Me (Me = Cu, Ag) was ~90:10 and was controlled by the diameter of the dispersible metal wires. Mesoporous AlOOH-Me composite were fabricated by the environmentally friendly process of Al-Me nanoparticles water oxidation at 60°Ϲ. The kinetic regularities of the Al-Me nanoparticles conversion in diluted aqueous suspensions were studied. The influence of second metal on the structure, morphology and antibacterial activity of nanocomposites against methicillin-resistance Staphylococcus aureus (MRSA) was investigated. The synthesized AlOOH-Me nanocomposites possessed high antibacterial activity. The results indicated that the as prepared AlOOH(Me) composite have a potential application in biomedical applications.

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Dontsova, Tetiana А., Olena I. Yanushevska, Svitlana V. Nahirniak, Anastasiya S. Kutuzova, Grigory V. Krymets, and Petro S. Smertenko. "Characterization of Commercial TiO2 P90 Modified with ZnO by the Impregnation Method." Journal of Chemistry 2021 (April 5, 2021): 1–11. http://dx.doi.org/10.1155/2021/9378490.

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This article is devoted to TiO2/ZnO nanocomposites’ creation by modifying with the commercial TiO2/P90 product using the impregnation method and identifying the effect of the ZnO modifier on its adsorption, structural, photocatalytic, and electrical properties. The synthesized TiO2/ZnO nanocomposites were characterized by XRD, XRF, XPS, and low-temperature nitrogen adsorption-desorption methods. As a result, nanostructured TiO2/ZnO composites with the ZnO content of 2, 5, 10, and 15% were obtained. It was shown that the phase composition of TiO2/P90 does not change during the nanocomposite synthesis. XPS studies of TiO2/ZnO nanocomposites indicated the presence of Ti4+, Zn2+, O2−, and OH states on their surface, which is associated with TiO2, ZnO, and hydroxide ions. The nitrogen adsorption-desorption method showed that the commercial TiO2/P90 sample is nonporous, and all TiO2/ZnO nanocomposites are characterized by almost the same homogeneous mesoporous structure. Experimentally established sorption and photocatalytic properties depend on the specific surface area and electrostatic interaction with dyes. The effect of the ZnO modifier on I-V characteristics of the TiO2/P90 sample was revealed. The obtained experimental data showed that the TiO2/P90 sample contains one type of current carriers, and TiO2/2ZnO and TiO2/5ZnO nanocomposites are characterized by two types of current carriers.

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Bakina, O. V., S. O. Kazantsev, A. V. Pervikov, E. A. Glazkova, N. V. Svarovskaya, A. S. Lozhkomoev, and E. G. Khorobraya. "Structure, Morphology, and Antibacterial Properties of Mesoporous AlOOH–Metal Nanocomposites." Inorganic Materials: Applied Research 12, no. 3 (May 2021): 767–75. http://dx.doi.org/10.1134/s2075113321030035.

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18

Massasso, G., M. Rodriguez-Castillo, J. Long, A. Grandjean, B. Onida, Y. Guari, Ch Guerin, and J. Larionova. "Nanocomposites based on Hofmann-type structure NiII(pz)[NiII(CN)4] (pz = pyrazine) nanoparticles for reversible iodine capture." Journal of Materials Chemistry A 3, no. 1 (2015): 179–88. http://dx.doi.org/10.1039/c4ta04855e.

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Hybrid nanocomposites based on nanoparticles with the Hofmann-type structure Ni^II(pz)[Ni^II(CN)₄] (where pz = pyrazine) confined into mesoporous silica or porous glass pearls were synthesised and studied for efficient iodine capture from solution.

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Jan, Jeng Shiung, Po Jui Chen, and Yu Han Ho. "Synthesis of Gold Nanoparticle/Silica Nanostructures." Materials Science Forum 688 (June 2011): 321–25. http://dx.doi.org/10.4028/www.scientific.net/msf.688.321.

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A novel approach is proposed to prepare organic-inorganic composite tubular structure by mineralizing silica and/or gold nanoparticle in the LbL assembled polypeptide multilayers films. Mesoporous silica (m-SiO2) and gold nanoparticle/mesoporous silica (Au NP/m-SiO2) tubes were prepared by subsequent calcination. The LbL assembled poly-L-lysine (PLL)/poly-L-tyrosine (PLT) multilayer film within the inner pores of polycarbonate templates acts as both a mineralizing agent and template for the formation of these materials. The as-prepared mesoporous SiO2and Au NP/m-SiO2tubes have well-defined structures. Gold nanoparticles with size smaller than 8 nm were immobilized in the silica network and the as-prepared Au NP/m-SiO2tubes exhibit good catalytic activity towards the reduction of p-nitrophenol. This approach may provide a facile and general method to synthesize organic-inorganic and metal-oxide nanocomposites with different composition and structures.

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Ghaffari, Yasaman, Md Saifuddin, Suho Kim, Soyoung Beak, Jiyeol Bae, and Kwang Soo Kim. "A Novel Metal-Containing Mesoporous Silica Composite for the Decolorization of Rhodamine B: Effect of Metal Content on Structure and Performance." Nanomaterials 12, no. 23 (November 22, 2022): 4108. http://dx.doi.org/10.3390/nano12234108.

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A series of novel MnxFey@SiO2 (x,y = 1–20%) nanocomposites were synthesized for the first time via the sol-gel/combustion method with different content of precursors (Mn and Fe acetate salts). The effect of precursor content and ratio on physicochemical properties were observed by various characterization methods. Moreover, Rhodamine B (RhB) was chosen as the target pollutant to test the performance of these nanocomposites under a photocatalytic Fenton-like reaction. The results showed that the nanocomposite morphology improved by increasing Fe and Mn content. In this study, interesting behavior was observed in BET results which were different from the fact that increasing metal content can decrease the surface area. This study revealed that one metal could be more critical in controlling the properties than another. Moreover, the precursor ratio appears to have a more tangible effect on the surface area than the effect of precursor content. Among all synthesized nanocomposites, Mn1Fe5@SiO2 showed the highest surface area of 654.95 m2/g. At optimum batch conditions (temp = 25 °C, catalyst dosage = 1 g L−1, H2O2 = 75 mmolL−1, and initial RhB concentration = 50 mg L−1), complete removal (simultaneous adsorption/degradation) occurred using Mn1Fe5@SiO2 at neutral pH. This study showed that the designed nanomaterial could be used as a dual functional adsorbent/photocatalyst in different environmental applications.

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Sadykov, Vladislav, Natalia Mezentseva, Vladimir Usoltsev, Oleg Smorygo, Vitali Mikutski, Alexander Marukovich, Oleg Bobrenok, and Nikolai Uvarov. "Metal Supported SOFC on the Gradient Permeable Metal Foam Substrate." Advanced Materials Research 123-125 (August 2010): 1083–86. http://dx.doi.org/10.4028/www.scientific.net/amr.123-125.1083.

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Gradient permeable metallic substrate material consisting of two layers of NiAl alloy was developed for the SOFC design. The open-cell foam layer (thickness 1-2 mm, cell density 60 ppi) provides the structure robustness, while a thin (100-200 μm) mesoporous layer facilitates supporting functional layers. Cathode layers (LSM, LSFN and their nanocomposites with GDC or YSZ) and anode layers (NiO/YSZ, NiO/YSZ +Ru/Ln-Sr-Mn-Cr-O nanocomposite catalyst) were deposited by slip casting, electrophoretic deposition or air brushing. Thin (5-10 μm) YSZ layer was deposited by MO CVD. Power density up to 550 mW/cm2 at 700oC was obtained on button-size cells using wet H2-air feeds.

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Wang, Zhao, Gao, Xu, Wang, and Zhu. "Multifunctional NaLnF4@MOF-Ln Nanocomposites with Dual-Mode Luminescence for Drug Delivery and Cell Imaging." Nanomaterials 9, no. 9 (September 6, 2019): 1274. http://dx.doi.org/10.3390/nano9091274.

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Multifunctional nanomaterials for bioprobe and drug carrier have drawn great attention for their applications in the early monitoring the progression and treatment of cancers. In this work, we have developed new multifunctional water-soluble NaLnF4@MOF-Ln nanocomposites with dual-mode luminescence, which is based on stokes luminescent mesoporous lanthanide metal–organic frameworks (MOFs-Y:Eu3+) and anti-stokes luminescent NaYF4:Tm3+/Yb3+ nanoparticles. The fluorescence mechanism and dynamics are investigated and the applications of these nanocomposites as bioprobes and drug carriers in the cancer imaging and treatment are explored. Our results demonstrate that these nanocomposites with the excellent two-color emission show great potential in drug delivery, cancer cell imaging, and treatment, which are attributed to the unique spatial structure and good biocompatibility characteristics of NaLnF4@MOF-Ln nanocomposites.

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Liao, Jieying, Huicong Zhang, and Xuandong Wang. "Polydopamine-doped virus-like mesoporous silica coated reduced graphene oxide nanosheets for chemo-photothermal synergetic therapy." Journal of Biomaterials Applications 35, no. 1 (April 11, 2020): 28–38. http://dx.doi.org/10.1177/0885328220916968.

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Multifunctional nanocarriers have been widely accepted and utilized for biomedical applications, because of their structural regularity, convenient post-modification and controllable structure and morphology. Herein, we reported polydopamine-doped virus-like mesoporous silica coated reduced graphene oxide nanosheets (rGO@PVMSNs) nanocomposites by a facile oil–water biphase stratification method. The synthesized rGO@PVMSNs nanocomposites performed excellent biocompatibility and photothermal performance. They could be employed as photoacoustic imaging contrast in vivo. Furthermore, the rGO@PVMSNs nanocarriers were used for loading the antitumor drug doxorubicin (DOX), the rGO@PVMSNs@DOX nanocomposites were also demonstrated to be with high inhibition of HepG2 cancer cells, especially with the help of near-infrared irradiation, which were more efficient than single chemotherapy or photothermal therapy. The rGO@PVMSNs@DOX nanocomposites of this work could be used as photoacoustic imaging and chemo-photothermal synergetic therapy agents, which show a new perspective for clinical tumor diagnosis and therapy.

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Bendeif, E. E., A. Gansmuller, K. Y. Hsieh, S. Pillet, Th Woike, M. Zobel, R. B. Neder, M. Bouazaoui, H. El Hamzaoui, and D. Schaniel. "Structure determination of molecular nanocomposites by combining pair distribution function analysis and solid-state NMR." RSC Advances 5, no. 12 (2015): 8895–902. http://dx.doi.org/10.1039/c4ra11470a.

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Total X-ray scattering coupled to atomic pair distribution function analysis (PDF) and solid state NMR allowed the identification and structural characterisation of isolated molecules and nanocrystals of sodium nitroprusside confined in mesoporous silica.

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25

Sharma, Swati, Ambika Verma, Ashok Kumar та Hesam Kamyab. "Magnetic Nano-Сomposites and their Industrial Applications". Nano Hybrids and Composites 20 (квітень 2018): 149–72. http://dx.doi.org/10.4028/www.scientific.net/nhc.20.149.

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Magnetic nanocomposites are multi-component, nanosized magnetic materials, to generate the response to an external stimulus (i.e., outer inert or alternative magnetic field). The novel nanocomposites is a combination of excess of various materials such as liquid crystals, silica, gels, renewable polymers, carbon along with different magnetic particles. They have immense applications in the field of medical diagnosis and therapy, catalysis and separation. These nanocarriers are mainly classified into nanotubes, nanosheets, spherical nanoparticles, nanofibres, highly porous nanocomposites. The porous nanostructures provides a better surface for the entrapment or covalent binding of enzymes, proteins, biomolecules and drugs but the major challenge is to design and synthesize a desired structure with suitable surface properties and biocompatibility. Extensive attempts have been made to manipulate the mesoporous materials and its combination with other structure in order to synthesize a matrix with appropriate pore size, large surface area to volume ratio. “Bottom-up” and “Bottom-down” chemical-based synthesis methods have been widely employed to prepare magnetic nanoparticles. Magnetic nanocomposites are synthesized from magnetic nanoparticles and biopolymers by using sol-gel technique, chemical precipitation methods and NanogenTM, a microwave plasma method. In this chapter, we described the advances and developments in the formation/synthesis of magnetic nanocomposites. This chapter will review the characteristics, properties and applications of the magnetic nanocomposites.

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26

CHENG, QILIN, VLADIMIR PAVLINEK, TOMAS BELZA, ANEZKA LENGALOVA, YING HE, and CHUNZHONG LI. "THE EFFECT OF POLYPYRROLE LOADING ON THE ELECTRORHEOLOGICAL PROPERTIES OF POLYPYRROLE/SBA-15 SUSPENSIONS." International Journal of Modern Physics B 21, no. 28n29 (November 10, 2007): 5026–32. http://dx.doi.org/10.1142/s0217979207045980.

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Encapsulated polypyrrole (PPy) with different amount in the channels of mesoporous silica (SBA-15) was synthesized. The XRD and N 2 adsorption/desorption isotherms analysis show that PPy with different loadings in the channels does not affect the ordered hexagonal structure of resultant PPy/SBA-15 nanocomposites. Further, the electrorheological (ER) properties of the nanocomposites with different PPy loadings were investigated by steady and oscillatory shear experiments. The results reveal that PPy/SBA-15 fluids exhibit typical ER and viscoelastic behavior under the applied electric field and ER response depends mainly on PPy loadings and there is an optimum PPy loading for strong ER effect.

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27

Wei, Yong, Xiaomin Li, Ahmed A. Elzatahry, Renyuan Zhang, Wenxing Wang, Xueting Tang, Jianping Yang, Jinxiu Wang, Daifallah Al-Dahyan, and Dongyuan Zhao. "A versatile in situ etching-growth strategy for synthesis of yolk–shell structured periodic mesoporous organosilica nanocomposites." RSC Advances 6, no. 56 (2016): 51470–79. http://dx.doi.org/10.1039/c6ra08541e.

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A versatile “in situetching-growth” strategy has been proposed to synthesize mesoporous composites with yolk–shell structure and controlled PMO shell, by combing the etching process with the shell growth.

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28

Matsukevich, I. V., E. D. Yundel, N. V. Kulinich, Y. A. Yahorava, L. V. Kulbitskaya, and T. F. Kuznetsova. "Preparation, structure and photocatalytic activity of nanocomposites based on cerium oxide." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 58, no. 4 (November 28, 2022): 351–59. http://dx.doi.org/10.29235/1561-8331-2022-58-4-351-359.

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Mesoporous CeO2 and MgO powders and nanocomposites based on them were synthesized by the method of self-propagating high-temperature synthesis, and the mutual influence of magnesium oxide and cerium oxide on the crystal structure, microstructure, and morphology of the obtained materials was studied. It has been established that CeO2 is formed on the surface of magnesium oxide, while the developed surface of the material is preserved. It has been established, that the sizes of CeO2 crystallites in the composition of nanocomposites change insignificantly and range from 6.5 to 7.4 nm, while the values of the specific surface area and average pore diameter of the studied samples depend on the composition and vary in the ranges of 19–41 m2/g and 11.9‒19 nm, respectively. The highest efficiency of photodegradation of dyes of acid telon blue and direct bright blue is observed for samples of MgO–CeO2 (30 mol.%) and MgO–CeO2 (50 mol.%) ‒ 98.5 and 92.5 %, respectively, taking into account the effect of direct photolytic decomposition under the influence of ultraviolet radiation.

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Yi, Guiyun, Baolin Xing, Huihui Zeng, Xiaodong Wang, Chuanxiang Zhang, Jianliang Cao, and Lunjian Chen. "One-Step Synthesis of Hierarchical Micro-Mesoporous SiO2/Reduced Graphene Oxide Nanocomposites for Adsorption of Aqueous Cr(VI)." Journal of Nanomaterials 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/6286549.

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A novel micro-mesostructured SiO2/reduced graphene oxide (RGO) nanocomposite was successfully synthesized by means of simple one-step hydrothermal method under acidic conditions using tetraethoxysilane (TEOS) and graphene oxide (GO) as the raw material. The nanocomposites were characterized by TEM, XRD, FT-IR, TG-DSC, and N2 adsorption-desorption. The results showed that GO was partially reduced to RGO without adding any reducing agent and SiO2 nanoparticles (ca. 10 nm) were uniformly anchored on the surface of RGO. The optimized composite contained 75 wt.% SiO2 and possessed hierarchical micro-mesoporous structure with surface area of 676 m2/g. The adsorption performance of synthesized SiO2/RGO samples was investigated by removal efficiency of Cr(VI) ions in wastewater. The Cr(VI) adsorption reached equilibrium in 30 min and 98.8% Cr(VI) adsorption efficiency was achieved at pH = 2 at 35°C. Stability tests showed that SiO2 nanoparticles effectively prevented RGO from the restacking. The mechanisms of composite formation and for Cr(VI) adsorption were suggested.

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Pal, Sudipto, Antonietta Taurino, Massimo Catalano, and Antonio Licciulli. "Block Copolymer and Cellulose Templated Mesoporous TiO2-SiO2 Nanocomposite as Superior Photocatalyst." Catalysts 12, no. 7 (July 12, 2022): 770. http://dx.doi.org/10.3390/catal12070770.

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A dual soft-templating method was developed to produce highly crystalline and mesoporous TiO2-SiO2 nanocomposites. Pluronic F127 as the structure-directing agent and pure cellulose as the surface area modifier were used as the templating media. While Pluronic F127 served as the sacrificing media for generating a mesoporous structure in an acidic pH, cellulose templating helped to increase the specific surface area without affecting the mesoporosity of the TiO2-SiO2 nanostructures. Calcination at elevated temperature removed all the organics and formed pure inorganic TiO2-SiO2 composites as revealed by TGA and FTIR analyses. An optimum amount of SiO2 insertion in the TiO2 matrix increased the thermal stability of the crystalline anatase phase. BET surface area measurement along with low angle XRD revealed the formation of a mesoporous structure in the composites. The photocatalytic activity was evaluated by the degradation of Rhodamine B, Methylene Blue, and 4-Nitrophenol as the model pollutants under solar light irradiation, where the superior photo-degradation activity of Pluronic F127/cellulose templated TiO2-SiO2 was observed compared to pure Pluronic templated composite and commercial Evonik P25 TiO2. The higher photocatalytic activity was achieved due to the higher thermal stability of the nanocrystalline anatase phase, the mesoporosity, and the higher specific surface area.

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de Kort, Laura Maria, Petra E. de Jongh, and Peter Ngene. "(Digital Presentation) Nanoscaffold Porosity and Surface Chemistry Effects on Li-Ion Conductivity in Metal Hydride Nanocomposite Electrolytes." ECS Meeting Abstracts MA2022-01, no. 47 (July 7, 2022): 1977. http://dx.doi.org/10.1149/ma2022-01471977mtgabs.

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The development of energy storage technologies, such as rechargeable batteries, is crucial for the transition to a sustainable energy supply. Lithium-ion batteries are an effective means of energy storage, which is demonstrated by their wide application ranging from mobile phones to laptops and electric vehicles. Unfortunately, Li-ion batteries suffer from safety issues arising from their combustible organic electrolytes. All-solid-state batteries, in which the common liquid organic electrolyte is replaced by a solid-state electrolyte, could potentially lead to safer batteries with increased energy density.[1] Recently, metal hydrides (e.g. LiBH4 and LiCB11H12) have gained attention as promising solid electrolytes due to their electrochemical and thermal stability, low density and high ionic conductivity albeit at elevated temperatures. However, for successful incorporation of metal hydride electrolytes in all-solid-state batteries, sufficient ionic conductivity at room temperature is a prerequisite. Therefore, the development of strategies that enhance the room temperature conductivity in complex hydrides (10-8 S cm-1 for LiBH4) is of major importance. In this contribution, we combined two promising strategies to enhance ion mobility in metal hydrides, namely, partial ionic substitution[2] and nanoconfinement[3], which led to highly conductive metal hydride-based nanocomposites (Figure 1). Specifically, via partial ion substitution with LiNH2, followed by nanoconfinement in a mesoporous oxide scaffold, LiBH4-LiNH2/metal oxide nanocomposites with conductivities reaching 5x10-4 S cm-1 at 30 °C were obtained[4], compared to 2x10-8 S cm-1 for pure LiBH4. Interestingly, the conductivity of the LiBH4-LiNH2/metal oxide nanocomposites is strongly influenced by the chemical and physical nature of the mesoporous metal oxide. We systematically studied the influence of the scaffold properties on the conductivity of nanoconfined LiNH2-substituted LiBH4 using mesoporous silica scaffolds (SBA-15) with varying surface chemistry and pore structure. The conductivity varied over three orders of magnitude when tuning both the porosity and surface chemistry of the metal oxide scaffold.[5] Our study reveals that the LiBH4-LiNH2/metal oxide conductivity is affected by the chemical nature of the scaffold, similar to LiBH4/metal oxide nanocomposites. A conductivity improvement of a factor of two is achieved by changing the SiO2 (SBA-15) surface chemistry through alumination (Figure 2a). On the other hand, different from nanoconfined LiBH4, the conductivity of LiBH4-LiNH2/metal oxide nanocomposites is largely dictated by the pore structure of the scaffold, especially the pore volume (Figure 2b). Notably, the conductivity can be varied from 4x10-7 S cm-1 to 5x10-4 S cm-1 by increasing the scaffold pore volume from 0.51 to 1.00 cm3 g-1. Our work demonstrates that the origin of the conductivity enhancement in anion-substituted complex hydride-based nanocomposite electrolytes is different from other nanoconfined complex hydrides, e.g. LiBH4. In particular, for nanoconfined LiBH4-LiNH2, the conductivity improvement is attributed to stabilization of a highly conductive phase inside the scaffold pores, rather than the formation of a conductive interfacial layer at the hydride/oxide interface as observed for nanoconfined LiBH4. Thus, it is clear that the conductivity of metal hydride-based nanocomposite ion conductors is closely linked to the properties of scaffold material. The fundamental insights on the influence of scaffold properties on ion mobility in nanocomposite materials could be applicable to other cation- and anion substituted ion conductors as well. Thereby, this work provides useful insights for the design novel solid-state electrolytes with excellent ionic conductivity, crucial for the development of next generation batteries. References [1] Janek, Jürgen, and Zeier, Wolfgang G. "A solid future for battery development." Nature Energy 1.9 (2016): 1-4. [2] Maekawa, Hideki, et al. "Halide-stabilized LiBH4, a room-temperature lithium fast-ion conductor." Journal of the American Chemical Society 131.3 (2009): 894-895. [3] Blanchard, Didier, et al. "Nanoconfined LiBH4 as a fast lithium ion conductor." Advanced Functional Materials 25.2 (2015): 184-192 [4] Zettl, Roman, et al. "Combined Effects of Anion Substitution and Nanoconfinement on the Ionic Conductivity of Li-Based Complex Hydrides." The Journal of Physical Chemistry C 124.5 (2020): 2806-2816. [5] de Kort, Laura M., et al. "The effect of nanoscaffold porosity and surface chemistry on the Li-ion conductivity of LiBH4–LiNH2/metal oxide nanocomposites." Journal of Materials Chemistry A 8.39 (2020): 20687-20697. Figure 1

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32

Song, Lee-hwa, Sung Nam Lim, Kyoung-Ku Kang, and Seung Bin Park. "Graphene-based mesoporous nanocomposites of spherical shape with a 2-D layered structure." Journal of Materials Chemistry A 1, no. 23 (2013): 6719. http://dx.doi.org/10.1039/c3ta10899f.

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Lee, Shu Chin, Hendrik O. Lintang, and Yuliati Leny. "Synthesis and Characterization of Zinc Phthalocyanine/Mesoporous Carbon Nitride Nanocomposites." Advanced Materials Research 364 (October 2011): 363–67. http://dx.doi.org/10.4028/www.scientific.net/amr.364.363.

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In this work, zinc phthalocyanine (ZnPc) was impregnated onto mesoporous carbon nitride (m-C3N4) to expand its absorption to longer wavelength. Nitrogen adsorption-desorption isotherm confirmed that the m-C3N4 showed type IV of adsorption-desorption isotherm. Transmission electron microscopy (TEM) revealed the presence of both nanosphere and nanoworm structure in the m-C3N4. Thermogravimetric analysis (TGA) showed that the synthesized m-C3N4 was thermally stable until 723 K. The presence of ZnPc on the m-C3N4 was confirmed from the X-ray diffraction (XRD) patterns and diffuse reflectance ultraviolet-visible (DR UV-Vis) spectra. The higher the amount of ZnPc loaded on m-C3N4, the higher the intensity of ZnPc peaks in the diffraction patterns. The successful impregnation of ZnPc onto the m-C3N4 was also supported by the color changing of the solids from yellow to blue, which can be seen as an additional broad band at 500-900 nm from the absorption spectra. Since the material gives visible light absorption, it is expected that the ZnPc/m-C3N4 would be a potential photocatalyst for reactions conducted under visible light irradiation.

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Alhaddad, Maha, and M. H. H. Mahmoud. "Improved Hg2+ photocatalytic reduction over g-C3N4 nanosheets decorated with mesoporous Mn3O4 nanoparticles." Materials Express 11, no. 5 (May 1, 2021): 688–98. http://dx.doi.org/10.1166/mex.2021.1958.

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The purpose of this investigation was to construct amended mesoporous Mn3O4/g-C3 N4 photocatalysts of various loadings of mesoporous Mn3O4 nanoparticles (1,2,3 and 4 wt%) for reinforced remediation of mercury ions (Hg2+) under visible light illumination. It was performed via decorating g-C3N4 nanosheets with finite portions of the prepared mesoporous Mn3O4 NPs by employing hard and soft templates. The optimized 3 wt% Mn3O4/g-C3N4 heterojunction gained confined bandgap (2.24 eV) as well as great surface area (140 m2 g -1) that support the application of such heterojunction for efficacious removal of Hg2+ under visible light. Morphological examination elucidated that the dispersed Mn3O4 NPs over g-C3N4 nanosheets were of spherical shape with particle dimension of 10-15 nm. Hg2+ was removed significantly over the formed Mn3O4/g-C3N4 nanocomposites when related to the pure materials (Mn3O4 NPs and g-C3N4). It was confirmed that Mn3O4 content, incorporated to g-C3N4 nanosheets, largely influenced the efficiency corresponding to the Hg2+ photoreduction such that appropriating 3 wt% Mn3O4 was capable of accomplishing complete removal of Hg2+ whereas, pure g-C3N 4was able to accomplish the same process by the efficiency of 15% after illumination for 60 min. Similarly, fast rate of Hg2+ photoreduction was accessed when 3% Mn3O4/g-C3N4 nanocomposite (485 µmol g–1 h–1) was administered while the photoreduction reaction was very slow with smaller rate magnitudes when pure g-C3N 4(82 µmol g -1 h -1) or pure Mn3O4 NPs (120 µmol g -1 h -1) were adopted. The powerful Hg2+ removal over the established heterojunctions can basically be associated with the larger attained surface area as well as the declined bandgap. Besides, the great dispersion of the small-sized Mn3O4 NPs and the mesoporous structure of the formed heterojunctions participated significantly in efficient Hg2+ removal. The improved characteristics of the prepared heterojunctions led to strong absorption of visible light and fast transference of reactant species, leading to enhanced photocatalytic efficiency. Recyclability experiments demonstrated that neither the photocatalytic performance nor the structure of the mesoporous Mn3O4/g-C3N4 heterojunction was altered after being reused for Hg2+ removal from aqueous solutions.

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Bendeif, EL-Eulmi, Kuan-Ying Hsieh, Dominik Schaniel, Axel Gansmuller, Sébastien Pillet, and Theo Woike. "Multiscale structure-properties analysis of photoactive nanocomposite materials." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C739. http://dx.doi.org/10.1107/s2053273314092602.

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In the last decades, the confinement of various types of functional material in mesoporous silica matrices has been used to design hybrid organic-inorganic nanocomposites with unique and fascinating properties. Such nanocomposites have attracted considerable interest owing to their potential applications in various domains [1-2], while reports with precise structural information of such molecular nanomaterials are still rather scarce and quite disparate. However, in order to be able to derive a structure-functionality relationship of such hybrid complexes, a detailed description of the structural organisation of the guest species and of their immediate surrounding is absolutely mandatory. We show in this contribution that detailed structural information can be obtained by using an appropriate multiscale approach combining various experimental techniques such as X-ray total scattering coupled to atomic pair distribution function (PDF) and solid-state NMR spectroscopy. This multiscale approach does provide more extensive and accurate structural information [3]. The PDF approach has allowed the identification of the nature of the incorporated species and their arrangement as well as the distinction of the various existing phases: isolated molecules and nanoparticles. The multi-nuclei Solid State NMR investigation has provided information on both the amorphous host and the molecular guest and adds a dynamic dimension to the classical static structural characterisation. We also discuss the influence of the structural changes on the physical properties of the investigated materials

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Yan, Zhiying, Zijuan He, Mi Li, Lin Zhang, Yao Luo, Jiao He, Yongjuan Chen, and Jiaqiang Wang. "Curcumin Doped SiO2/TiO2 Nanocomposites for Enhanced Photocatalytic Reduction of Cr (VI) under Visible Light." Catalysts 10, no. 8 (August 17, 2020): 942. http://dx.doi.org/10.3390/catal10080942.

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In order to further improve the photocatalytic performance of the SiO2/TiO2 composite under visible light irradiation, curcumin-doped SiO2/TiO2 nanocomposites were synthesized via directly incorporating it into the structure of SiO2/TiO2 during the synthesis using an inexpensive and readily available natural pigment (curcumin) as doping agent. The physicochemical properties of SiO2/TiO2 nanocomposites were characterized in detail by X-ray diffraction, transmission electron microscopy, Fourier transform-infrared spectroscopy, N2 adsorption–desorption isotherms, X-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectroscopy. The results indicate that all SiO2/TiO2 nanocomposites exhibited an anatase phase with a typical mesoporous structure. It was found that the dope of curcumin in the SiO2/TiO2 composite could decrease the crystal size, slightly improve the specific surface areas, significantly enhance the visible light absorption, and effectively narrow the band gap energy from 3.04 to 10(eV). Compared with bare SiO2/TiO2, the curcumin-doped SiO2/TiO2 resulted in enhanced photocatalytic reduction activity for Cr(VI) under visible light irradiation, and the CTS (12) sample with the appropriate content of curcumin of 12 wt % shows the photocatalytic yield reaching 100% within 2.5 hours, which is larger than CT (12) without silica. This could be attributed to the curcumin doping and the synergetic effects of SiO2 and TiO2 in SiO2/TiO2 nanocomposites.

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Zhang, Fa-Ai, Dong-Keun Lee, and Thomas J. Pinnavaia. "PMMA/mesoporous silica nanocomposites: effect of framework structure and pore size on thermomechanical properties." Polym. Chem. 1, no. 1 (2010): 107–13. http://dx.doi.org/10.1039/b9py00232d.

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Guerritore, Marco, Rachele Castaldo, Brigida Silvestri, Roberto Avolio, Mariacristina Cocca, Maria Emanuela Errico, Maurizio Avella, Gennaro Gentile, and Veronica Ambrogi. "Hyper-Crosslinked Polymer Nanocomposites Containing Mesoporous Silica Nanoparticles with Enhanced Adsorption Towards Polar Dyes." Polymers 12, no. 6 (June 20, 2020): 1388. http://dx.doi.org/10.3390/polym12061388.

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The development of new styrene-based hyper-crosslinked nanocomposites (HCLN) containing mesoporous silica nanoparticles (MSN) is reported here as a new strategy to obtain functional high surface area materials with an enhanced hydrophilic character. The HCLN composition, morphology and porous structure were analyzed using a multi-technique approach. The HCLN displayed a high surface area (above 1600 m2/g) and higher microporosity than the corresponding hyper-crosslinked neat resin. The enhanced adsorption properties of the HCLN towards polar organic dyes was demonstrated through the adsorption of a reactive dye, Remazol Brilliant Blue R (RB). In particular, the HCLN containing 5phr MSN showed the highest adsorption capacity of RB.

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Wang, Manchao, Lin Peng, Jiahui Wang, Changqing Li, Lihao Guan, and Yuqing Lin. "Enhanced Visible Light Photocatalytic Decolorization of Methylene Blue by Hierarchical Ternary Nanocomposites Cu–TiO2-Mesoporous-Silica Microsphere." Journal of Nanoscience and Nanotechnology 18, no. 12 (December 1, 2018): 8269–75. http://dx.doi.org/10.1166/jnn.2018.16405.

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In this study, hierarchical ternary nanocomposites, i.e., Cu–TiO2-mesoporous silica microspheres (Cu–TiO2-MSM), were synthesized as ternary photocatalyst system to improve the visible light photocatalytic degradation of the environmental pollutant model dye methylene blue (MB). The innovation of this method is in situ depositing TiO2 and Cu2O nanoparticles sequentially onto the surface of mesoporous silica microspheres to form highly active heterostructure. The improved activity for the degradation of MB is attributed to: (1) the high adsorption capacity of the porous and interconnected-channel-structure MSM to MB; (2) the valence band electrons of TiO2 released from the conduction band generating abundant highly active free radicals, which directly reacted with adsorbed MB. The photocatalytic degradation efficiency to MB was found to be 98% in 5 min, and almost 100% in 20 min. This study paves a way for the development of a ternary-doped catalyst for visible light photocatalytic degradation and may exhibit widely application in industry.

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40

Segale, Mayetu, Rudzani Sigwadi, and Touhami Mokrani. "The Impact of Mesoporous Silica Nanoparticles on Electrochemical Performance." Journal of Nano Research 79 (June 21, 2023): 49–60. http://dx.doi.org/10.4028/p-30r16t.

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Mesoporous silica nanoparticles were synthesized via sol–gel method to produce uniform size nanoparticles using n-Octadecyl-trimethoxy silane which gives a good dispersion of silica nanoparticles in hydrophobic mediums. Scanning electron microscopy (SEM), infrared spectroscopy, X-ray diffraction (XRD), thermal gravimetric analysis, and nitrogen adsorption-desorption tests were used to thoroughly investigate the nanocomposites' morphology and structure. BET results show a high surface are of 760 m2/g and specific high pore size (30Ȧ) and pore volume (0.336 cm3/g). The SEM results present that the mesoporous silica nanoparticles possess a well dispersed and uniform particle morphology and FTIR interpenetrating the well-prepared silica nanoparticles which possess Si-O-Si and Si-O bond. The XRD analysis confirmed the amorphous nature silica nanoparticles. The electrochemical properties of silica nanoparticles were evaluated in a potassium chloride solution. With the advantages of a large specific surface area and a suitable pore size distribution, a pair of broad and symmetric redox peaks centred at -0.15 V and 0.6 V appears. Mesoporous silica with a large effective specific surface area demonstrated excellent electrochemical performance, making them excellent candidates for supercapacitors and fuel cells.

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Liang, Sen, Xiao Zhang, Haibo Li, Min Luo, and Mangmang Gao. "Preparation of SiO2 nanocomposites with aligned distributing glass fibre using freeze-drying process." Processing and Application of Ceramics 11, no. 3 (2017): 201–5. http://dx.doi.org/10.2298/pac1703201l.

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The glass fibre reinforced nano-SiO2 composites (with up to 40 wt.% of glass fibres) as insulating materials were fabricated firstly by preparing aligned glass fibres under the ice formation followed by pressing and annealing. Scanning electron microscopy analyses confirmed the presence of parallel distribution of glass fibres in certain direction. The low-temperature nitrogen adsorption and mercury intrusion measurements showed that the composites have mesoporous structure with the mean pore size less than 20 nm. Further, it was found that the compressive strength and thermal conductivity of composite were 15.1MPa and 0.0585W/(m?K), respectively.

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Bopape, Dineo A., Sarah Mathobela, Nolubabalo Matinise, David E. Motaung, and Nomso C. Hintsho-Mbita. "Green Synthesis of CuO-TiO2 Nanoparticles for the Degradation of Organic Pollutants: Physical, Optical and Electrochemical Properties." Catalysts 13, no. 1 (January 10, 2023): 163. http://dx.doi.org/10.3390/catal13010163.

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CuO-TiO2 nanocomposites were successfully synthesized using the C. benghalensis plant extracts. The effect of the composition of CuO to TiO2 on the morphological, optical, electrochemical, and photodegradation efficiency in the composites was studied. SEM, XRD, UV-vis, FTIR, TGA, BET, and CV were used to characterize these materials. The XRD data reported the tenorite structure of the CuO and the anatase phase of the TiO2. SEM showed the spherical morphologies for all the CuO-TiO2 NPs, and these were also mesoporous in nature, as depicted by BET. The voltammogram of the CuO-TiO2 30/70 electrode showed a higher response current density compared to the other two samples, suggesting a higher specific capacitance. Upon testing the photocatalytic efficiencies of the CuO-TiO2 nanocomposites against methylene blue (MB), ciprofloxacin (CIP), and sulfisoxazole (SSX), the highest degradation of 94% was recorded for SSX using the CuO-TiO2 30/70 nanocomposites. Hydroxyl radicals were the primary species responsible for the photodegradation of SSX, and the material could be reused once. The most active species in the photodegradation of SSX has been identified as OH•. From this study, it can be noted that the CuO-TiO2 nanocomposites were more selective toward the degradation of antibiotics (sulfisoxazole and ciproflaxin) as compared to dyes (methylene blue).

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Volkov, A. V., V. V. Polyanskaya, M. A. Moskvina, S. B. Zezin, A. I. Dement’ev, A. L. Volynskii, and N. F. Bakeev. "Structure and properties of hybrid PP/TiO2 nanocomposites and mesoporous TiO2 prepared via solvent crazing." Nanotechnologies in Russia 7, no. 7-8 (July 2012): 377–84. http://dx.doi.org/10.1134/s1995078012040155.

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Vamvasakis, Ioannis, Evangelos K. Andreou, and Gerasimos S. Armatas. "Mesoporous Dual-Semiconductor ZnS/CdS Nanocomposites as Efficient Visible Light Photocatalysts for Hydrogen Generation." Nanomaterials 13, no. 17 (August 26, 2023): 2426. http://dx.doi.org/10.3390/nano13172426.

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The development of functional catalysts for the photogeneration of hydrogen (H2) via water-splitting is crucial in the pursuit of sustainable energy solutions. To that end, metal-sulfide semiconductors, such as CdS and ZnS, can play a significant role in the process due to their interesting optoelectronic and catalytic properties. However, inefficient charge-carrier dissociation and poor photochemical stability remain significant limitations to photocatalytic efficiency. Herein, dual-semiconductor nanocomposites of ZnS/CdS nanocrystal assemblies (NCAs) are developed as efficient visible light photocatalysts for H2 generation. The resultant materials, synthesized via a polymer-templated self-polymerization method, comprise a unique combination of ~5–7 nm-sized metal-sulfide nanoparticles that are interlinked to form a 3D open-pore structure with large internal surface area (up to 285 m2 g−1) and uniform pores (circa 6–7 nm). By adjusting the ratio of constituent nanoparticles, the optimized ZnS/CdS catalyst with 50 wt.% ZnS content demonstrates a remarkable stability and visible light H2-evolution activity (~29 mmol g−1 h−1 mass activity) with an apparent quantum yield (AQY) of 60% at 420 nm. Photocatalytic evaluation experiments combined with electrochemical and spectroscopic studies suggest that the superior photocatalytic performance of these materials stems from the accessible 3D open-pore structure and the efficient defect-mediated charge transfer mechanism at the ZnS/CdS nanointerfaces. Overall, this work provides a new perspective for designing functional and stable photocatalytic materials for sustainable H2 production.

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Zhao, Yongbin, Jianhua Zou, Wenfang Shi, and Longxiang Tang. "Preparation and characterization of mesoporous silica spheres with bimodal pore structure from silica/hyperbranched polyester nanocomposites." Microporous and Mesoporous Materials 92, no. 1-3 (June 2006): 251–58. http://dx.doi.org/10.1016/j.micromeso.2006.01.007.

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Mao, Huihui, Xiaoting Liu, Jihe Yang, Baoshan Li, Qun Chen, and Jing Zhong. "Fabrication of magnetic silica-pillared clay (SPC) nanocomposites with ordered interlayer mesoporous structure for controlled drug release." Microporous and Mesoporous Materials 184 (January 2014): 169–76. http://dx.doi.org/10.1016/j.micromeso.2013.10.020.

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Chang, Baisong, Xurui Zhang, Jia Guo, Yang Sun, Hongyan Tang, Qingguang Ren, and Wuli Yang. "General one-pot strategy to prepare multifunctional nanocomposites with hydrophilic colloidal nanoparticles core/mesoporous silica shell structure." Journal of Colloid and Interface Science 377, no. 1 (July 2012): 64–75. http://dx.doi.org/10.1016/j.jcis.2012.03.082.

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Mohapatra, Dillip Kumar, Swetapadma Praharaj, and Dibyaranjan Rout. "Electrochemical charge storage performance of mesoporous MoO₃@Co₃O₄ nanocomposites as electrode materials." Nanotechnology 33, no. 15 (January 21, 2022): 155709. http://dx.doi.org/10.1088/1361-6528/ac467e.

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Abstract Constructing a novel nanocomposite structure based on Co3O4 is of the current interest to design and develop efficient electrochemical capacitors. The capacitive performance of MoO3@Co3O4 nanocomposite is compared with pristine Co3O4 nanoparticles, both of them being synthesized by hydrothermal technique. A BET surface area of ∼41 m2 g−1 (almost twice that of Co3O4 ) and average pore size of 3.6 nm is found to be suitable for promoting Faradaic reactions in the nanocomposite. Electrochemical measurements conducted on both samples predict capacitive behavior with quasi-reversible redox reactions. MoO3@Co3O4 nanocomposite is capable of delivering a superior specific capacitance of 1248 F g−1 at 0.5 A g−1 along with notable stability of 92% even after 2000 cycles of charge–discharge and Coulombic efficiency approaching 100% at 10 A g−1. The outstanding results obtained in this work assure functional adequacy of MoO3@Co3O4 nanocomposite in fabricating high-performance electrochemical capacitors.

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Romanovska, N. I., P. A. Manorik, V. S. Vorobets, G. Ya Kolbasov, N. I. Ermokhina, Y. V. Kishenya, S. O. Sotnik, P. S. Yaremov, and A. V. Polishchuk. "Effect of Conditions of Sol-Gel Synthesis and Post-Synthetic Treatment on Photoelectrochemical and Electro-Catalytic Properties of Titanium Oxide Nanostructures and Tio2-Au Nanocomposites." Elektronnaya Obrabotka Materialov 57, no. 4 (August 2021): 1–14. http://dx.doi.org/10.52577/eom.2021.57.4.01.

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Carbon-doped mesoporous TiO2 nanostructures and TiO2-Au nanocomposites with stabilized Au nanoparticles have been synthesized by the sol-gel template method and characterized by X-ray diffraction, scanning and transmission electron microscopies, Fourier-transform infrared spectroscopy, N2 adsorption/desorption, ultraviolet-visible spectroscopy, and photoelectrochemical current spectroscopy. The synthesis hydrothermal treatment conditions affected the particle size, electronic structure, morphology, phase, and chemical compositions, as well as the texture of the synthesized materials. The TiO2 and TiO2-Au based electrodes were light-sensitive in a wavelength range of 250–412 nm and were distinguished by a high catalytic activity during oxygen electroreduction. The presence of -ol and carboxylate groups in the amorphous phase is the main factor affecting the photosensitivity of TiO2 nanostructures to visible light and an increase in their photoactivity during the decomposition of methylene blue upon irradiation with ultraviolet and visible light relative to pure anatase. The higher photosensitivity and photoactivity of TiO2-Au nanocomposites compared with those of the corresponding starting TiO2 is due to the synergistic effect of Au nanoparticles and interstitial Ti-O-C groups, which depends on the Au nanoparticle content of the composite and on the mesopore size.

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Banerjee, Shilpi, and Dipankar Chakravorty. "Multifunctional Mesoporous Nanocomposites." Materials Science Forum 736 (December 2012): 98–119. http://dx.doi.org/10.4028/www.scientific.net/msf.736.98.

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Multifunctional behaviour viz., ferroelectric, ferromagnetic and magnetodielectric coupling has been reported in a number of nanocomposites. The latter were synthesized by growing nanoparticles of different kinds within a suitable matrix. Different morphologies of the particles were introduced. Both natural as well as synthetic mesoporous materials were used to prepare nanocomposite systems. Mesoporous structures with large surface areas and pore volumes were found to be effective in developing most efficient drug delivery systems. For identical reasons such structures were suitable as catalysts in various industrially important reaction processes, as humidity and gas sensors, as magnetic sensors. Mesoporous carbon based nanocomposites used as electrodes were found to improve the efficiency of lithium-ion batteries. Nanocomposites using mesoporous carbon and carbon nanotubes were shown to improve the performance of dye sensitized solar cells. In this article, the above mentioned developments are reviewed and discussed.

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