Journal articles: 'Electron-catalytic method'

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Cruz-Reyes, J., M. Avalos-Borja, M. H. Farias, and S. Fuentes. "Electron Microscopy in hydrodesulfurization catalysts." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 4 (August 1990): 260–61. http://dx.doi.org/10.1017/s0424820100174436.

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Applications of transition metal sulfides for hydroprocessing catalysts have included a variety of reactions. It is generally believed that an interaction between the active phase (Mo or W) and the promoter (Co or Ni) takes place. Several models have been suggested to explain the enhanced catalytic activity. The catalytic properties of the unsupported sulfides are dependent on the catalyst preparation methods . In this work we study by electron microscopy two sets of unsupported samples ranging from molybdenum sulfide to cobalt sulfide. The specimens were prepared by the following methods, a slight variation of the classical homogeneous sulfide precipitation (HSP) method, and a new method called impregnated thiosalt decomposition (ITD).

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Chuanyu, Sun, and Wang Yu. "Synthesis of polyaniline nanotubes through UV light catalytic method." Materials Science-Poland 33, no. 1 (March 1, 2015): 193–97. http://dx.doi.org/10.1515/msp-2015-0022.

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AbstractIn this study, nitrocellulose (NC) fiber blanket prepared by electrostatic spinning method has been used as a template, and copper nitrate (Cu(NO3)2) as an oxidant to synthesise polyaniline nanotubes doped with heteropolyacid (H4SiW12O40, SiW12) using UV light catalytic method. Infrared spectroscopy (IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) technologies were applied to characterize the prepared samples of polyaniline nanotubes. The results show that the external diameter of the tube is about 200 nm, and the internal diameter about 170 nm. We also give a reasonable speculation and explanation about the formation mechanism of the nanotubes.

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Nhu, Vo Thi Thu, Nguyen Ngoc Duy, Huynh Nguyen Anh Tuan, Nguyen Pham Tu Ngan, Do Quang Minh, and Nguyen Quoc Hien. "PHOTOCATALYTIC DEGRADATION OF RHODAMINE B USING Ag NANO DOPED TiO2 PREPARED BY -IRRADIATION METHOD." Vietnam Journal of Science and Technology 54, no. 4 (August 18, 2016): 494. http://dx.doi.org/10.15625/0866-708x/54/4/7201.

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Ag nano deposited on TiO2 (Degussa P25) (Ag nano/TiO2) photo-catalyst has been synthesized by g-irradiation method. The characteristics of Ag nano/TiO2 material has been investigated by BET surface area, X-ray diffraction (XRD), transmission electron microscopy (TEM) and the diffuse reflectance spectra (DRS). The photo-catalytic properties of Ag nano/TiO2 for degradation of Rhodamine B in aqueous solution under visible light have been studied. Results indicated that Ag nano/TiO2 photo-catalyst exhibited better photo-catalytic activity compared to that of TiO2 under the same reaction condition. The higher activity of Ag nano/TiO2 is due the enhancement of electron–hole separation effect on the surface of the catalyst. At 1.5% Ag doping content, the Ag nano/ TiO2 photo-catalyst exhibited the highest photo-catalytic activity under visible light.

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Phan Thi To, Nga, Lien Nguyen Hong, Tuyen Le Van, Nhan Phan Chi, and Huyen Pham Thanh. "Synthesis of porous LaFeO3 prepared by nanocasting method for photo-Fenton degradation of oily-containing wastewater." Vietnam Journal of Catalysis and Adsorption 11, no. 1 (June 30, 2021): xx. http://dx.doi.org/10.51316/jca.2022.002.

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Porous LaFeO3 were synthesised by nanocasting method using mesoporous silica (SBA-15) as a hard template and used as a visible-light-driven photocatalyst. The as-synthesised LaFeO3 photocatalyst were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray Diffraction (XRD), N2 adsorption-desorption, and Ultraviolet–Visible Diffuse Reflectance Spectroscopy (UV-vis DRS). The photo-Fenton catalytic activities of porous LaFeO3 were investigated for the degradation of oily-containing wastewater. The results showed that porous LaFeO3 had better photo-Fenton catalytic activity under visilbe light irradiation than pure LaFeO3. The remarkable improvement photo-Fenton catalytic activity of porous LaFeO3 material could be attributed to the synergistic effect of adsorption and visible light photo-Fenton processes thanks to its porous structure.

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Wang, Xixin, Jianling Zhao, Xiaorui Hou, Qi He, and Chengchun Tang. "Catalytic Activity of ZrO2Nanotube Arrays Prepared by Anodization Method." Journal of Nanomaterials 2012 (2012): 1–5. http://dx.doi.org/10.1155/2012/409571.

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ZrO2nanotube arrays were prepared by anodization method in aqueous electrolyte containing (NH4)2SO4and NH4F. The morphology and structure of nanotube arrays were characterized through scanning electron microscope, X-ray diffraction, and infrared spectra analysis. The zirconia nanotube arrays were used as catalyst in esterification reaction. The effects of calcination temperature and electrolyte concentration on catalytic esterification activity have been investigated in detail. Experiments indicate that nanotube arrays have highest catalytic activity when the concentration of (NH4)2SO4is 1 mol/L, the concentration of NH4F is 1 wt%, and the calcination temperature is 400°C. Esterification reaction yield of as much as 97% could be obtained under optimal conditions.

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Xian, Guang, Nan Zhang, Guangming Zhang, Yi Zhang, and Zhiguo Zou. "FeNiCeOx ternary catalyst prepared by ultrasonic impregnation method for diclofenac removal in Fenton-like system." Water Science and Technology 79, no. 9 (May 1, 2019): 1675–84. http://dx.doi.org/10.2166/wst.2019.166.

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Abstract FeNiCeOx was firstly prepared by ultrasonic impregnation method and used to remove diclofenac in a Fenton-like system. The catalytic activity was improved successfully by doping Ni into FeCeOx. The diclofenac removal efficiency reached 97.9% after 30 min reaction. The surface morphology and properties of FeNiCeOx were characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Raman and X-ray photoelectron spectroscopy (XPS) analyses. FeNiCeOx in this paper had larger specific surface area than those prepared by other methods, which was attributed to the cavitation effect and hot-spot effect during the ultrasonic synthesis process. Low crystallinity of Fe2O3 and NiO showed by characterization could lead to high interaction of Fe and Ni ions with support of CeO2. They substituted Ce in CeO2, caused lattice contraction and formed more oxygen vacancies, which favoured the catalytic reaction. Meanwhile, Fe and Ce ions both had redox cycles of Fe3+/Fe2+ and Ce4+/Ce3+, which facilitated the electron transfer in the reaction. The synergistic effect among Fe, Ni and Ce might lead to better catalytic performance of FeNiCeOx than any binary metal oxides constituted from the above three elements. Finally, the potential mechanism of diclofenac removal in FeNiCeOx-H2O2 system is proposed.

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Pan, Feng, Jun Ying Zhang, Hai Ying Liu, Tian Min Wang, and Wei Chang Hao. "Ag Nanoparticle Enhanced Photocatalytic Activity of Rutile TiO₂ Films Prepared by Electrostatic Self-Assembly Method." Key Engineering Materials 280-283 (February 2007): 293–96. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.293.

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Ag nano-particles were deposited on the surface of TiO2 self-assembled films by photo-reduction of Ag+ solution. SPM, XPS and UV-Vis spectrophotometer were employed to characterize the microstructure and photo-catalytic performance of the films. An obvious enhancement of photo-catalytic activity had been observed. Since rutile had a lower optical band gap than anatase, a higher photo-catalytic efficiency improvement of rutile than that of anatase was obtained under the help of Ag nano-particles, which acted as electron acceptors.

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Wang, Ming Rui, Wen Jiang Li, and Mei Ling Pan. "Preparation of CuS Hollow Microsphere by a Simple Hydrothermal Method and its Catalytic Property." Advanced Materials Research 535-537 (June 2012): 329–32. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.329.

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A simple method was applied to fabricate phase-pure hollow CuS microspheres. The obtained product was characterized by X-ray diffraction, scanning electron microscopy, photoluminescence spectra and UV-Vis absorption spectroscopy. Further, the catalytic activity of CuS spheres was evaluated by the decolorization of Rhodamine B in the presence of hydrogen peroxide solution at room temperature. The results indicated that the product showed a good optical propertie, and the hollow sphere CuS could be an effective catalytic material.

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Zhu, Guang, Xiao Ping Zou, Jin Cheng, Fei Li, Hong Dan Zhang, Peng Fei Ren, and Mao Fa Wang. "Catalytic Combustion Synthesis of Carbon Nanofibers." Materials Science Forum 561-565 (October 2007): 1537–40. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.1537.

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The catalytic combustion technique was used to synthesize carbon nanotubes and carbon nanofibers. In this paper, we report that carbon nanofibers were synthesized by ethanol catalytic combustion technique. The as-grown products were characterized by means of scanning electron microscopy, transmission electron microscopy, Raman spectroscopy. The results showed that the products have a mass of carbon nanofibers. However, morphology and microstructure of carbon nanofibers are affected by synthesis conditions, such as stability of flames and sampling time, sampling temperature etc. Different Influence factors were depicted in detail. Ethanol catalytic combustion technique offer a simple method to synthesize carbon nanotubes and carbon nanofibers, it also has some advantages, such as flexible synthesis conditions, simple setup, and environment-friendly.

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Zhong, Kaifu, Pu Jin, and Qianwang Chen. "Ni Hollow Nanospheres: Preparation and Catalytic Activity." Journal of Nanomaterials 2006 (2006): 1–7. http://dx.doi.org/10.1155/jnm/2006/37375.

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A method to prepare monodispersed silica nanospheres as templates for fabrication of nickel-silica composite hollow spheres is presented. The structures for both silica nanospheres and nickel-silica composite hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The catalytic activity for acetone hydrogenation on nickel-silica composite hollow spheres was evaluated, and high conversion efficiency of 70% with good selectivity of 82.7% to 2-propanol was observed. The mechanism of high catalytic activity and good selectivity in acetone hydrogenation reaction was discussed.

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Dong, Lifeng, and Jun Jiao. "Electron Microscopy Study of Exotic Nanostructures of Cadmium Sulfide." Microscopy and Microanalysis 11, no. 2 (March 8, 2005): 116–23. http://dx.doi.org/10.1017/s1431927605050166.

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In this article, two simple methods, evaporation-condensation and catalytic thermal evaporation, were used to investigate the synthesis of CdS nanostructures for nanoscale optoelectronic applications. To understand their growth mechanisms, various electron microscopy and microanalysis techniques were utilized in characterizing their morphologies, internal structures, growth directions and elemental compositions. The electron microscopy study reveals that when using the evaporation-condensation method, branched CdS nanorods and self-assembled arrays of CdS nanorods were synthesized at 800°C and 1000°C, respectively. Instead of morphological differences, both types of CdS nanorods grew along the [0001] direction. However, when using the catalytic thermal evaporation method (Au as the catalyst), patterned CdS nanowires and nanobelts were formed at the temperature region of 500–600°C and 600–750°C, respectively. Their growth direction was along the direction [1010] instead of [0001]. Based on the microscopy and microanalysis results, we propose some growth mechanisms in relation to the growth processes of those exotic CdS nanostructures.

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Yang, Li Li, Lin Yu, and Gui Qiang Diao. "Synthesis of Novel Functional Materials for the Photo-Catalytic Reaction." Advanced Materials Research 774-776 (September 2013): 868–71. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.868.

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Zeolitic imidazolate frameworks-8(ZIF-8, Zn (MIM) 2, MIM=2-methylimidazole) was synthesized by solvothermal (S) method and liquid-phase diffusion (D) method. ZIF-8 was then directly impregnated with phosphortungstic acid (PTA) at room temperature. After impregnation, the ZIF-8 retained its integrity of frameworks as proved by several characterizations. The textural properties are heavily dependent on preparation methods. Diffusion method produced well-crystallized particles with larger surface area, whereas solvothermal method yielded poorly-crystallized particles. ZIF-8 and ZIF-8-PTA were applied in the photo-degradation of methylene blue (MB) with the assistance of electron acceptor hydrogen peroxide, in which both of them were found to be highly active photo-catalytic. Moreover, the impregnation of PTA improved clearly the activity of catalysts due to the fast reversible multi-electron redox transformations.

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Kuettel, M. R., S. P. Squinto, J. Kwast-Welfeld, G. Schwoch, J. S. Schweppe, and R. A. Jungmann. "Localization of nuclear subunits of cyclic AMP-dependent protein kinase by the immunocolloidal gold method." Journal of Cell Biology 101, no. 3 (September 1, 1985): 965–75. http://dx.doi.org/10.1083/jcb.101.3.965.

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An immunocolloidal gold electron microscopy method is described allowing the ultrastructural localization and quantitation of the regulatory subunits RI and RII and the catalytic subunit C of cAMP-dependent protein kinase. Using a postembedding indirect immunogold labeling procedure that employs specific antisera, the catalytic and regulatory subunits were localized in electron-dense regions of the nucleus and in cytoplasmic areas with a minimum of nonspecific staining. Antigenic domains were localized in regions of the heterochromatin, nucleolus, interchromatin granules, and in the endoplasmic reticulum of different cell types, such as rat hepatocytes, ovarian granulosa cells, and spermatogonia, as well as cultured H4IIE hepatoma cells. Morphometric quantitation of the relative staining density of nuclear antigens indicated a marked modulation of the number of subunits per unit area under various physiologic conditions. For instance, following partial hepatectomy in rats, the staining density of the nuclear RI and C subunits was markedly increased 16 h after surgery. Glucagon treatment of rats increased the staining density of only the nuclear catalytic subunit. Dibutyryl cAMP treatment of H4IIE hepatoma cells led to a marked increase in the nuclear staining density of all three subunits of cAMP-dependent protein kinase. These studies demonstrate that specific antisera against cAMP-dependent protein kinase subunits may be used in combination with immunogold electron microscopy to identify the ultrastructural location of the subunits and to provide a semi-quantitative estimate of their relative cellular density.

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Bendieb Aberkane, Amar, María Pilar Yeste, Djazi Fayçal, Daniel Goma, and Miguel Ángel Cauqui. "Catalytic Soot Oxidation Activity of NiO–CeO2 Catalysts Prepared by a Coprecipitation Method: Influence of the Preparation pH on the Catalytic Performance." Materials 12, no. 20 (October 21, 2019): 3436. http://dx.doi.org/10.3390/ma12203436.

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A series of NiO–CeO2 mixed oxide catalysts have been synthesized by a modified coprecipitation method at three different pH values (pH = 8, 9, and 10). The NiO–CeO2 mixed oxide samples were characterized by TGA, XRD, inductively coupled plasma atomic emission spectroscopy (ICP-AES), FTIR, Brunauer–Emmett–Teller (BET) surface area, H2 temperature-programmed reduction (H2-TPR), and electron microscopy (high-angle annular dark-field transmission electron microscopy/energy-dispersive X-ray spectroscopy (HAADF-TEM/EDS)). The catalytic activities of the samples for soot oxidation were investigated under loose and tight contact conditions. The catalysts exhibited a high BET surface area with average crystal sizes that varied with the pH values. Electron microscopy results showed the formation of small crystallites (~5 nm) of CeO2 supported on large plate-shaped particles of NiO (~20 nm thick). XRD showed that a proportion of the Ni2+ was incorporated into the ceria network, and it appeared that the amount on Ni2+ that replaced Ce4+ was higher when the synthesis of the mixed oxides was carried out at a lower pH. Among the synthesized catalysts, Ni-Ce-8 (pH = 8) exhibited the best catalytic performance.

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ARUNKUMAR, S., S. CHIDAMBARA VINAYAGAM, S. LAKSHMANAN, and S. ARUL ANTONY. "Citrus Extract Modified Graphene Oxide as a Green and Heterogeneous Organocatalyst for the Synthesis of Imidazole Derivatives." Asian Journal of Chemistry 32, no. 9 (2020): 2375–80. http://dx.doi.org/10.14233/ajchem.2020.22578.

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A naturally benign convention was created with a surface change of graphene oxide by citrus extract as catalyst was prepared by a straight-forward chemical modification method. The prepared catalyst′s catalytic activity was examined by the synthesis of imidazole derivatives at room temperature. It shows a strong acidic catalytic and sustainable organocatalyst. The prepared catalyst was characterized using different analytical procedures like elemental analysis, Fourier transforms infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), energy-dispersive X-ray analysis (EDS), scanning electron microscopy images (SEM) and transmission electron microscopy images (TEM) analysis. The catalytic activity shows high activity and can be reused without significant loss of catalytic activity after five times. A present catalyst works easily under room temperature.

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Zakharova, D. S., I. V. Martynov, V. M. Nosova, and O. N. Temkin. "CATIONIC PD(II) COMPLEXES CATALYTICALLY ACTIVE IN THE OXIDATION OF OLEFINS : MECHANISMS OF THE FORMATION IN WATER -ACETONITRILE -CHLORIC ACID MEDIUM." Fine Chemical Technologies 11, no. 2 (April 28, 2016): 57–65. http://dx.doi.org/10.32362/2410-6593-2016-11-2-57-65.

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The catalytic system Pd (OAc)2-HClO4--CH3CN (AN)-H2O of olefins oxidation was studied. Information about the ways of forming catalytic active cationic palladium complexes was detected. Analysis of the electron spectroscopy data shows the probability of existence complexes [Pd(AN)(H2O)3]2+ (λmax = 360-365 nm), [Pd(AN)2(H2O)2]2+ (λmax = 335-345 nm) in catalytic system. The preparation method of stable and sufficient active catalytic system for obtaining reproducible kinetic data was designed.

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Gbashi, Kadhim Rashid. "Synthesis and characterization of carbon nanospheres by catalytic CVD method." Iraqi Journal of Physics (IJP) 15, no. 35 (October 2, 2018): 75–82. http://dx.doi.org/10.30723/ijp.v15i35.55.

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Carbon nanospheres (CNSs) were successfully prepared and synthesized by Catalytic Chemical Vapor Deposition (CCVD) by using camphor as carbon source only, over iron Cobalt (Fe-Co) saturated zeolite at temperature between (700 oC and 900 °C), with different concentrations of camphor, and reaction time. The synthesized CNSs were characterized using Scanning Electron Microscopy (SEM), X-ray diffraction spectroscopy (XRD), and Fourier Transform Infrared (FTIR). The carbon spheres in different sizes between 100 nm and 1000 nm were investigated. This work has done by two parts, first preparation of the metallic catalyst and second part formation CNSs by heat treatment.

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Kappis, Konstantinos, Christos Papadopoulos, Joan Papavasiliou, John Vakros, Yiannis Georgiou, Yiannis Deligiannakis, and George Avgouropoulos. "Tuning the Catalytic Properties of Copper-Promoted Nanoceria via a Hydrothermal Method." Catalysts 9, no. 2 (February 1, 2019): 138. http://dx.doi.org/10.3390/catal9020138.

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Copper-cerium mixed oxide catalysts have gained ground over the years in the field of heterogeneous catalysis and especially in CO oxidation reaction due to their remarkable performance. In this study, a series of highly active, atomically dispersed copper-ceria nanocatalysts were synthesized via appropriate tuning of a novel hydrothermal method. Various physicochemical techniques including electron paramagnetic resonance (EPR) spectroscopy, X-ray diffraction (XRD), N2 adsorption, scanning electron microscopy (SEM), Raman spectroscopy, and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) were employed in the characterization of the synthesized materials, while all the catalysts were evaluated in the CO oxidation reaction. Moreover, discussion of the employed mechanism during hydrothermal route was provided. The observed catalytic activity in CO oxidation reaction was strongly dependent on the nanostructured morphology, oxygen vacancy concentration, and nature of atomically dispersed Cu2+ clusters.

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Jia, Ying, Tian Tian Liu, and Cheng Luo. "Study of Hydrothermal Synthesis of Ce_0.67Zr_0.33O₂ Nanorods and Catalytic Property to CO." Advanced Materials Research 347-353 (October 2011): 615–20. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.615.

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Ce0.67Zr0.33O2 (CZ) nanorods are successfully synthesized by glycol-assisted hydrothermal method using zirconium oxychloride, cerium nitrate and urea, with the presence of sodium hypochlorite. The products are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectra. The catalytic oxidation characters about Pd/CZ three-way catalyst (TWC) prepared with different loads of Pd are also investigated. The results show that the as-prepared Pd/CZ has excellent catalytic oxidation character to CO.

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Manafi, S. A., and S. H. Badiee. "Production of Carbon Nanofibers Using a CVD Method with Lithium Fluoride as a Supported Cobalt Catalyst." Research Letters in Materials Science 2008 (2008): 1–5. http://dx.doi.org/10.1155/2008/850975.

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Carbon nanofibers (CNFs) have been synthesized in high yield (>70%) by catalytic chemical vapor deposition (CCVD) on Co/LiF catalyst using acetylene as carbon source. A novel catalyst support (LiF) is reported for the first time as an alternative for large-scale production of carbon nanofibers while purification process of nanofibers is easier. In our experiment, the sealed furnace was heated at700∘Cfor 0.5 hour (the heating rate was10∘C/min) and then cooled to room temperature in the furnace naturally. Catalytic chemical vapor deposition is of interest for fundamental understanding and improvement of commercial synthesis of carbon nanofibers (CNFs). The obtained sample was sequentially washed with ethanol, dilutes acid, and distilled water to remove residual impurities, amorphous carbon materials, and remaining of catalyst, and then dried at110∘Cfor 24 hours. The combined physical characterization through several techniques, such as high-resolution transmission electron microscope (TEM), scanning electron microscope (SEM), thermogarvimetric analysis (TGA), and zeta-sizer and Raman spectroscopy, allows determining the geometric characteristic and the microstructure of individual carbon nanofibers. Catalytic chemical vapor deposition is of interest for fundamental understanding and improvement of commercial synthesis of carbon nanofibers (CNFs). As a matter of fact, the method of CCVD guarantees the production of CNFs for different applications.

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Zhao, Shusen, and Dongxu Ma. "Preparation of Co Nanocrystallites by Solvothermal Process and Its Catalytic Activity on the Thermal Decomposition of Ammonium Perchlorate." Journal of Nanomaterials 2010 (2010): 1–5. http://dx.doi.org/10.1155/2010/842816.

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Nanometer cobalt ferrite (Co) was synthesized by polyol-medium solvothermal method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). Further, the catalytic activity and kinetic parameters of Co nanocrystallites on the thermal decomposition behavior of ammonium perchlorate (AP) have been investigated by thermogravimetry and differential scanning calorimetry analysis (TG-DSC). The results imply that the catalytic performance of Co nanocrystallites is significant and the decrease in the activation energy and the increase in the rate constant for AP further confirm the enhancement in catalytic activity of Co nanocrystallites. A mechanism based on an proton transfer process has also been proposed for AP in the presence of Co nanocrystallites.

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Janjua, Muhammad Ramzan Saeed Ashraf. "Synthesis of Co3O4 Nano Aggregates by Co-precipitation Method and its Catalytic and Fuel Additive Applications." Open Chemistry 17, no. 1 (October 16, 2019): 865–73. http://dx.doi.org/10.1515/chem-2019-0100.

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AbstractThe nano aggregates of cobalt oxide (Co3O4) are synthesized successfully by adopting simple a co precipitation approach. The product obtained was further subjected to the calcination process that not only changed it morphology but also reduces the size of individual particles of aggregates. The prepared nano aggregates are subjected to different characterization techniques such as electron microscopies (scanning electron microscopy and transmission electron microscopy) and X-ray diffraction and results obtained by these instruments are analyzed by different software. The characterization results show that, although the arrangement of particles is compact, several intrinsic spaces and small holes/ pores can also be seen in any aggregate of the product. The as synthesized product is further tested for catalytic properties in thermal decomposition of ammonium perchlorate and proved to be an efficient catalyst.

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Peña, Armando, Julio Puerta, Aimé Guerrero, Edgar Cañizales, and Joaquín L. Brito. "Catalytic Chemical Vapor Deposition Synthesis of Carbon Aerogels of High-Surface Area and Porosity." Journal of Nanotechnology 2012 (2012): 1–5. http://dx.doi.org/10.1155/2012/708626.

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In this work carbon aerogels were synthesized by catalytic chemical vapor deposition method (CCVD). Ferrocene were employed as a source both of catalytic material (Fe) and of carbon. Gaseous hydrogen and argon were used as reductant and carrier gas, respectively. The products of reaction were collected over alumina. The morphology and textural properties of the soot produced in the reaction chamber were investigated using Scanning Electron Microscopy, High-Resolution Transmission Electron Microscopy, X-ray photoelectron spectroscopy, and N2physisorption (BET and BHJ methods). After the evaluation of the porous structure of the synthesized products, 780 ± 20 m2/g ofSBETand 0.55 ± 0.02 cm3/g ofVBJHwere found. The presence of iron carbide and the partial oxidation of carbon nanostructures were revealed by XPS.

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Cao, Maojiong, Youyong Su, Bing Xue, Yuxiang Yang, and Xiangnong Liu. "Effect of Crystallization on the Catalytic Cracking Performance of Zeolite Socony Mobil-5." Journal of Nanoscience and Nanotechnology 18, no. 12 (December 1, 2018): 8437–46. http://dx.doi.org/10.1166/jnn.2018.16376.

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In the research, zeolite socony mobil-5 (ZSM-5) catalyst was prepared by hydrothermal method and characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), NH3-temperature programmed desorption (NH3-TPD) and Brunauer- Emmett-Teller (BET). The catalytic products from Jatropha carcass L. oil were analyzed by gas chromatography-mass spectrometer (GC-MS). The effects of crystallization time and crystallization temperature on catalytic cracking performance of ZSM-5 were investigated. According to the results, the catalytic cracking performance of ZSM-5 was closely associated with its pore structure. When the crystallization time was 60 h and the crystallization temperature was 170 °C, ZSM-5 with optimal catalytic cracking performance was synthesized. Catalyzed by the optimal ZSM-5, Jatropha carcass L. oil showed the liquid conversion rate of 26.60% and the acid value of 1.24 mg KOH·g−1. The main catalytic products from Jatropha carcass L. oil included benzene (10.02%), methylbenzene (20.52%), o-xylene (14.45%) and p-xylene (6.59%).

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Yan, Xue Min, and Yuan Zhu Mi. "Effect of Preparation Methods of HPW/SiO₂ Mesoporous Composites on its Catalytic Performance in Fuel Oils Desulfurization." Advanced Materials Research 148-149 (October 2010): 924–28. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.924.

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Two kinds of mesoporous HPW/SiO2 composites, which have been synthesized respectively by the amino-functionalized (AF) method and evaporation-induced self-assembly (EISA) method, have been used as catalysts in the oxidative desulfurization process of dibenzothiophene(DBT). The catalytic performance results show that the catalyst synthesized by EISA method holds higher catalytic activity than that synthesized by the AF method. The difference of catalytic activity can be attributed to the different synthesis mechanism of two kinds of composites. In the AF method, the bonding force between HPW and SiO2 is strong acid-base interaction, which damages the Keggin structure. Whereas in the EISA process, electrostatic force and hydrogen bonds between W=O groups and Si-OH groups are main bonding forces. The hydrogen bond holds the electron-withdrawing effect, which increases the activity of nonbonding W=O groups in HPW and then results in the enhancement of the catalytic activity.

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López-Moreno, Alejandro, David Clemente-Tejeda, Joaquín Calbo, Atena Naeimi, Francisco A. Bermejo, Enrique Ortí, and Emilio M. Pérez. "Biomimetic oxidation of pyrene and related aromatic hydrocarbons. Unexpected electron accepting abilities of pyrenequinones." Chem. Commun. 50, no. 66 (2014): 9372–75. http://dx.doi.org/10.1039/c4cc04026k.

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Maryam, M., A. B. Suriani, M. S. Shamsudin, and Mohamad Rusop Mahmood. "Synthesis of Carbon Nanotubes from Palm Oil Precursor by Aerosol-Assisted Catalytic CVD Method." Applied Mechanics and Materials 229-231 (November 2012): 247–51. http://dx.doi.org/10.4028/www.scientific.net/amm.229-231.247.

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Carbon nanotubes were produced from the aerosol-assisted catalytic CVD method using palm oil as the precursor and ferrocene as the catalyst. The CNTs were yielded at optimized temperature of 700oC and the Field Emission Scanning Electron Microscope showed the image of CNTs produced. Raman Spectroscopy, energy dispersive X-ray and Thermogravimetric Analysis were then used to further study the Raman Spectra, purity and identification of samples.

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Li, Sai Sai, Jun Kai Wang, Qing Zhu, Xiao Wei Zhao, and Hai Jun Zhang. "Fabrication of Graphitic Carbon Spheres via a Hydrothermal Carbonization Combined Catalytic Graphitization Method Using Cobalt as Catalysts." Solid State Phenomena 281 (August 2018): 807–12. http://dx.doi.org/10.4028/www.scientific.net/ssp.281.807.

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Graphitic carbon spheres (GCS) with an average diameter of 1.6 μm were prepared via a hydrothermal carbonization combined catalytic graphitization method using glucose as carbon source and cobalt nitrate as catalyst precursor. The as-prepared GCS were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. It was found that the optimal weight ratio of Co catalyst for graphitization of amorphous carbonaceous spheres was 2.0 wt%, and the optimal temperature and dwelling time required for graphitization were respectively 1100 °C and 3 h.

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Ai, Chaoqian, Yaoyao Zhang, Pan Wang, and Wei Wang. "Catalytic Combustion of Diesel Soot on Ce/Zr Series Catalysts Prepared by Sol-Gel Method." Catalysts 9, no. 8 (July 29, 2019): 646. http://dx.doi.org/10.3390/catal9080646.

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Cerium-zirconium (Ce-Zr) solid solutions have been extensively used in a wide variety of catalytic processes due to their unique catalytic features in conjunction with lower cost compared to noble metal-based systems. A series of Ce-Zr-based catalysts was prepared by the sol-gel method. The structure and morphology of these catalysts were characterized by X-ray diffraction, thermogravimetric-differential scanning calorimetry, scanning electron microscopy, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy. Furthermore, investigation on catalytic performance was carried out by constructing a test platform, and the result indicated that the catalysts apparently decreased the soot ignition temperature. These catalysts exhibited higher catalytic activity for soot oxidation under narrow contact conditions. The results revealed that some soot particles could react with adsorbed oxygen, and other part of diesel soot reacted with lattice oxygen. The activity of these catalysts was attributed to synergistic effect arising from the combination of K/Co/Zr and Ce-Zr solid solution, which led to the decrease in the ignition temperature to 294 °C (data from the test platform). The catalyst still keeps good stability and catalytic activity after the cycle oxidation experiment. A reaction pathway was proposed to explain catalytic combustion process of soot, i.e., combination of K/Co/Zr with Ce-Zr solid solution reduced the binding energy of Ce-Zr solid solution, which was conducive to provide more active sites to release the active oxygen (O2−) or lattice oxygen (O2−).

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Wei, Chuanying, Haili Hou, Ermo Wang, and Min Lu. "Preparation of a Series of Pd@UIO-66 by a Double-Solvent Method and Its Catalytic Performance for Toluene Oxidation." Materials 13, no. 1 (December 23, 2019): 88. http://dx.doi.org/10.3390/ma13010088.

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This paper reports on the preparation, characterization, and catalytic properties of the Pd@UIO-66 for toluene oxidation. The samples are prepared by the double-solvent method to form catalysts with large specific surface area, highly dispersed Pd0 (Elemental palladium) and abundant adsorbed oxygen, which are characterized by X-ray Photoelectron Spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and Transmission Electron Microscopy (TEM). The results show that as the Pd content increases, the adsorbed oxygen content further increases, but at the same time Pd0 will agglomerate and lose some active sites, which will affect its catalytic performance. While 0.2%Pd@UIO-66 has the highest concentration of Pd0, the result shows it has the best catalytic activity and the T90 temperature is 210 °C.

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Lu, Xi, Shuqian Xie, Shuai Li, Jun Zhou, Wenquan Sun, Yanhua Xu, and Yongjun Sun. "Treatment of Purified Terephthalic Acid Wastewater by Ozone Catalytic Oxidation Method." Water 13, no. 14 (July 9, 2021): 1906. http://dx.doi.org/10.3390/w13141906.

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In this study, a Cu–Ce@Az ozone catalyst with multiple active components was prepared through the impregnation method to treat purified terephthalic acid (PTA) wastewater, and characterized by X-ray diffraction, X-ray fluorescence spectroscopy, scanning electron microscopy, specific surface area analysis, X-ray energy spectroscopy, X-ray photoelectron spectroscopy, and other methods. The Cu–Ce@Az ozone catalyst had a developed pore structure with a large specific surface area and crystal structure. After calcination, the metallic elements Cu and Ce existed in the state of oxides CuO and CeO2. The effects of reaction time, solution pH, catalyst dosage, and ozone dosage on the catalytic oxidation performance of the Cu–Ce@Az ozone catalyst were studied. Adding tert-butanol reduced the removal rate of COD from the PTA wastewater through the catalytic oxidation system, which proves that a Cu–Ce@Az ozone catalyst treatment process of PTA wastewater follows the free-radical reaction mechanism. The results of 3D fluorescence spectroscopy analysis show that the organic matter in the PTA wastewater was converted into tryptophan organic matter and aromatic organic matter after the reaction of the catalytic oxidation system. Ultraviolet absorption spectroscopy analysis indicated that in unsaturated chemical bonds, some conjugated structures and benzene ring structures of organic matter in the PTA wastewater were destroyed.

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Li, Li Min, San Kui Xu, Xiao Dong Wang, Nan Nan Guo, Yun Lai Su, and Peng Zhang. "Preparation of CuO/γ-Al₂O₃ Catalysts by Impregnationin Supercritical CO₂." Advanced Materials Research 396-398 (November 2011): 1313–17. http://dx.doi.org/10.4028/www.scientific.net/amr.396-398.1313.

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CuO/γ-Al2O3 catalysts were prepared by supercritical CO2 (SC-CO2) impregnation method. The preparation was carried out in SC-CO2 with Cu(NO3)2 as precursor, methanol as assistant solvent, and γ-Al2O3 as support. The effects of impregnation parameters such as temperature and pressure of SC-CO2, impregnation time, ratio of precursor to support, and amount of assistant solvent on catalyst preparation were investigated. The as-prepared catalysts were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis and compared to that prepared by the conventional impregnation method. The SC-CO2 impregnation method provided higher adsorption rate, larger adsorption quantity, more homogeneous dispersion of precursor, and stronger interaction between precursor and support. The catalytic degradation of methylene blue (MB) was used as probe reaction to estimate the catalytic activity of two catalysts prepared by two methods. The catalyst prepared by SC-CO2 impregnation method exhibits significantly improved catalytic activity. These results show that the inorganic metallic reagents as precursor with assistant solvent can be used as an alternative for the organometallic precursors in SC-CO2 impregnation method.

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Lubis, Khairiza, Nuannoi Chudapongse, Hau Van Doan, and Oratai Weeranantanapan. "Characterization of Biocompatible Gold Nanoparticles Synthesized by using Curcuma xanthorrhiza and their Catalytic Activity." Current Nanoscience 16, no. 2 (March 26, 2020): 214–25. http://dx.doi.org/10.2174/1573413715666181128142258.

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Background: Based on various distinguished physical and chemical properties of gold nanoparticles, they have far wide applications in several areas of industry and medicine, such as catalysis, bio-sensor and drug delivery. Compared to a chemical method, biological synthesis is an economical and less toxic process, thus it is a better alternative for nanoparticle synthesis. In this study, an environmentally friendly method was chosen to produce AuNPs using Curcuma xanthorrhiza. Methods: Alkaline aqueous extract of C. xanthorrhiza rhizomes, which acts as a reducing and stabilizing agent was used to produce AuNPs by bio-reduction of HAuCl4. The formation of AuNPs was periodically monitored by UV-visible spectroscopy. The obtained AuNPs were characterized by Xray diffraction, energy dispersive spectroscopy, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared (FTIR) spectroscopy. Catalytic activity and toxicity of the AuNPs were evaluated. Results: The AuNPs obtained from this study mostly were spherical in shape with approximately 15 nm in size. The presence of functional groups derived from C. xanthorrhiza rhizome extract involved in the gold bio-reduction process was confirmed by the spectrum of FTIR spectroscopy. The biosynthesized AuNPs at the concentration of 0.5 μg/ml had catalytic activity in dye degradation of Congo red. The results showed that this biogenic AuNPs did not cause any toxicity to zebrafish embryos and all tested cell lines. Conclusion: The biocompatible AuNPs with catalytic activity were successfully fabricated with C. xanthorrhiza rhizome extract by simple eco-friendly and inexpensive method. This catalytic activity of the obtained AuNPs is potentially useful for industrial applications as well as nanoscience and nanotechnology.

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Gama-Lara, S. A., Raúl A. Morales-Luckie, L. Argueta-Figueroa, Juan P. Hinestroza, I. García-Orozco, and R. Natividad. "Synthesis, Characterization, and Catalytic Activity of Platinum Nanoparticles on Bovine-Bone Powder: A Novel Support." Journal of Nanomaterials 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/6482186.

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Pt nanoparticles supported on bovine-bone powder were obtained by a rather simple method consisting of immersing powder of bovine bone into a Pt+4 metal ion solution at room temperature and subsequent reduction by sodium borohydride. This method eliminates the calcination step of the usual catalyst preparation methods. The nanocomposite was characterized by transmission electron microscopy (TEM), which revealed uniformly dispersed platinum nanoparticles with average particle size of 2.2 nm ± 0.6 nm. The XPS studies exhibited the presence of 63% Pt° and 37% PtO. The catalytic activity was tested in the hydrogenation of 2-butyne-1,4-diol. The nanocomposite shows good catalytic performance with nearly 100% conversion and 83% selectivity towards 2-butene-1,4-diol.

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Zhang, Yu, Yalong Liao, Gongchu Shi, Wei Wang, and Bowen Su. "Preparation, characterization, and catalytic performance of Pd–Ni/AC bimetallic nano-catalysts." Green Processing and Synthesis 9, no. 1 (December 23, 2020): 760–69. http://dx.doi.org/10.1515/gps-2020-0071.

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AbstractPalladium–nickel (Pd–Ni) bimetallic nano-catalysts supported on activated carbon (Pd–Ni/AC) have been successfully prepared by impregnation method enhanced with ultrasonic. The prepared Pd–Ni/AC catalysts were used for the catalytic hydrodechlorination reaction of bleached shellac and characterized by Fourier-transform infrared spectroscopy, nitrogen adsorption, X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscope, and high-resolution transmission electron microscopy. The results show that Pd–Ni bimetallic structures in catalytic particles with the diameter of 4 and 14 nm were distributed uniformly on AC support, and the lattice fringe spacing in catalytic particles was measured as 0.213 nm which is lying in the region between monometallic Pd (111; 0.225 nm) and Ni (111; 0.203 nm), and that Pd1–Ni1/AC catalyst exhibits the best catalytic hydrodechlorination performance with the dechlorination efficiency of 92.58 wt% while it is used for the hydrodechlorination of bleached shellac, and the optimum catalytic performance is related to the synergistic electronic effect and bimetallic structure of the Pd1–Ni1/AC sample.

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Pakdee, U., N. Suttisiri, Ekachai Hoonnivathana, and S. Chiangga. "Synthesis of Coil-Like Shape CNTs by Thermal CVD Method." Advanced Materials Research 55-57 (August 2008): 541–44. http://dx.doi.org/10.4028/www.scientific.net/amr.55-57.541.

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The coil-like shape carbon nanotubes (CNTs) were synthesized on stainless steel substrates using acetylene gas (C2H2) at 750oC under pressure of 4110−× bar by thermal chemical vapor deposition (CVD) method. The formation of catalytic nanoparticles used hydrogen (H2) as the environment gas. The scanning electron microscope (SEM) image shown the average coil diameter of CNTs is 0.8µm and 0.1 nm for the average coil pitch of CNTs. The Raman spectrum shown the defect of CNTs and indicate that the carbon samples were tubes.

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Gerelbaatar, Khongorzul, Ariunzaya Tsogoo, Rentsenmyadag Dashzeveg, Ninjbadgar Tsedev, and Erdene Ochir Ganbold. "Reduction of 2,4-Dinitrophenol to 2,4-Diaminophenol Using AuNPs and AgNPs as Catalyst." Solid State Phenomena 271 (January 2018): 76–84. http://dx.doi.org/10.4028/www.scientific.net/ssp.271.76.

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In this study, colloidal metal nanoparticles have been prepared by the wet-chemical synthesis method. Gold and silver nanoparticles with approximate sphere shape were synthesized through the citrate-reduction method. The colloidal metal nanoparticles were characterized by using UV-vis absorption spectroscopy, photon cross-correlation spectroscopy (PCCS) and transmission electron microscope (TEM). Catalytic activities of the metal nanoparticles were investigated through reduction of 2,4-dinitrophenol to 2,4-diaminophenol in the presence of NaBH4 at room temperature. Both gold and silver nanoparticles showed an excellent catalytic activity.

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Le, Thien An, Jong Kyu Kang, Sae Ha Lee, and Eun Duck Park. "CO and CO2 Methanation Over Ni/γ-Al2O3 Prepared by Deposition-Precipitation Method." Journal of Nanoscience and Nanotechnology 19, no. 6 (June 1, 2019): 3252–62. http://dx.doi.org/10.1166/jnn.2019.16585.

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Various Ni catalysts supported on γ-Al2O3 were prepared by a wet impregnation (WI) method and deposition-precipitation (DP) method with different precipitants and applied to CO and CO2 methanation. The prepared catalysts were characterized by various techniques including nitrogen physisorption, X-ray diffraction (XRD), temperature-programmed reduction with H2 (H2-TPR), H2 chemisorption, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Irrespective of kinds of precipitant, the Ni/γ-Al2O3 catalysts prepared with a DP method showed a remarkable enhanced catalytic performance in CO and CO2 methanation compared with the Ni/γ-Al2O3 catalyst prepared with a WI method owing to the higher catalytic active surface area (CASA). In the case of Ni/γ-Al2O3 catalysts prepared with a DP method, the high calcination temperatures are not favorable for the high catalytic activity due to the decreased reduction degree of Ni oxide species and CASA. The reduction degree of Ni oxide species can be increased with reduction temperature. However, the higher reduction temperature above 500 °C is not desirable to achieve the high catalytic activity because of the decreased CASA. The selective CO methanation was also accomplished at lower temperatures over the Ni/γ-Al2O3 catalyst prepared with a DP method than over the Ni/γ-Al2O3 catalyst prepared with a WI method.

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Chen, Qingyun, Miao Zhou, Di Ma, and Dengwei Jing. "Effect of Preparation Parameters on Photoactivity of BiVO4by Hydrothermal Method." Journal of Nanomaterials 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/621254.

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Bismuth vanadate (BiVO4) was synthesized from a mixture of aqueous Bi(NO3)3and NH4VO3solutions by using hydrothermal method. Via conducting the orthogonal experiments and single-factor experiments, the best synthetic parameters were determined. The physical and photophysical properties of the as-obtained samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-Vis diffusion reflectance spectroscopy (UV-Vis). The result showed that the best experimental parameters of monoclinic BiVO4werepH=7,T=195 °C, and t=6 h. The catalytic performance of BiVO4was evaluated by reducing carbon dioxide to methane under visible light irradiation. It was found that the methane production reached 145 μg/g-cat after 5 h irradiation with the catalyst dosage of 0.15 g in 200 mL mixed solution of 0.1 M NaOH and 0.1 M Na2SO3.

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Putrasari, Yanuandri, P. Untoro, Sulaiman Hasan, Naili Huda, and Darwin Sebayang. "Modification of Surface Roughness and Area of FeCrAl Substrate for Catalytic Converter using Ultrasonic Treatment." Journal of Mechatronics, Electrical Power, and Vehicular Technology 1, no. 2 (March 9, 2012): 53–60. http://dx.doi.org/10.14203/j.mev.2010.v1.53-60.

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Surface roughness and area play important role especially in deposition and reaction of the catalyst in the catalytic converter substrate. The aim of this paper is to show the modification of surface roughness and area of FeCrAl substrate for catalytic converter using ultrasonic method. The method was conducted by agitating the FeCrAl in 10 minutes 35 kHz ultrasonic cleaning bath. The surface roughness, morphology, and chemical components of FeCrAl catalytic converter substrate after ultrasonic treatment were analyzed using atomic force microscope (AFM) and examined with scanning electron microscope (SEM) in combination with energy dispersive X-ray spectroscopy (EDS). The ultrasonic treatment assisted with Al2O3 powders successfully increased the roughness and surface area of FeCrAl better than SiC powders.

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Zhu, Min Cong, En Qiang Wang, Ying Chen Zhang, and Deng Xin Li. "Coupled ZnO/TiO₂ Nanorods Deposited in the Pores of Expanded Graphite Prepared by Microwave Irradiation." Advanced Materials Research 204-210 (February 2011): 268–72. http://dx.doi.org/10.4028/www.scientific.net/amr.204-210.268.

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Expanded graphite (EG) was prepared by microwave irradiation at 1000W for 60s. The growth of coupled ZnO/TiO2nanonods in the pores of EG by using hydrolysis method without harsh conditions was investigated and their microstructure was studied by scanning electron microscopy (SEM). Results show that pores of EG, which can load catalytic nanoparticles, is the physical base for growth of catalytic nanorods. The active edges of graphene of freshly EG is a key factor for the growth of coupled ZnO/TiO2nanorods under non-catalytic and normal temperature and pressure conditions.

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Liang, Renxiao, Huanfeng Jiang, and Shifa Zhu. "An efficient route to highly strained cyclobutenes: indium-catalyzed reactions of enynals with alkynes." Chemical Communications 51, no. 25 (2015): 5530–33. http://dx.doi.org/10.1039/c4cc08506j.

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A catalytic method to synthesize the highly strained cyclobutene was developed. The reaction was believed to proceed through a formal indium-catalyzed [2+2] cycloaddition between electron-deficient enynals and a variety of alkynes.

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Ding, Zhen Wu, Si Chen, Zhong Qing Liu, Cheng Fa Jiang, and Wei Chu. "Mesoporous Sulfur-Doped TiO₂ Microspheres for Catalytic Degradation of Methylene Blue under Visible Light." Advanced Materials Research 1118 (July 2015): 242–50. http://dx.doi.org/10.4028/www.scientific.net/amr.1118.242.

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Mesoporous S-doped TiO2 microspheres were synthesized via hydrothermal method using Ti (SO4)2 precursor and urea as homogeneous precipitate agent. The TiO2-based catalyst samples were characterized by means of Field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), N2 adsorption/desorption and UV-vis diffuse reflectance spectra (UV-vis DRS). Photo-catalytic experiments were carried out by catalytic degradation of methylene blue aqueous solution under visible light. It was found that the S-doped TiO2 microspheres gave better photo-catalytic performances. The higher absorbance in the visible region explained this phenomenon. There was an appropriate Ti (SO4)2 amount for the catalyst with better photo-catalytic degradation.

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He, Deng Liang, and Shi Xin Fang. "Preliminary Research on the Preparation of Ce-Doped TiO₂ by Sol Method." Advanced Materials Research 785-786 (September 2013): 745–48. http://dx.doi.org/10.4028/www.scientific.net/amr.785-786.745.

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butyl titanate, water and anhydrous ethanol were used as raw materials; Cerium-doped TiO2 was prepared by sol method at room temperature. Then it was characterized by X ray diffraction, Raman spectra, Uv-vis absorption spectra and Scanning Electron Microscope. The results show that TiO2 crystal can be got by sol method at room temperature. Cerium-doped TiO2 has the better catalytic performance for methyl orange.

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Xue, Gang, Xue Fang Zhang, Sai Fei Wang, and Chao Yue Zhao. "Preparation and Characterization of Perovskite-Type Oxide Catalysts for Combustion of Methane." Advanced Materials Research 427 (January 2012): 77–81. http://dx.doi.org/10.4028/www.scientific.net/amr.427.77.

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A series of rare earth perovskite-type oxides La09Sr0.1Co0.9Mn0.1O3La08Sr0.2Co0.8Mn0.2O3and La05Sr0.5Co0.5Mn0.5O3were prepared along the sol-gel method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy techniques (TEM) and catalytic activity measurement for combustion of CH4. The results indicated that a perfect crystal structure of perovskite was formed and La3+and Co3+ions were partly replaced by Sr2+and Mn3+ions, respectively, and perovskite-type oxides were composed of nanocrystals with particle size of 20~50nm. The catalytic activity for the combustion of CH4 was evaluated and La05Sr0.5Co0.5Mn0.5O3exhibited best performance with the temperature of 50% and 90% conversion efficiency of 723K and 833K.

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Li, Lin, Chen Zhang, Xinqing Chen, Peng Gao, Jian Sun, Hui Wang, and Yuhan Sun. "Preparation of Highly Dispersion CuO/MCM-41 Catalysts for CO2 Hydrogenation." Journal of Nanoscience and Nanotechnology 19, no. 6 (June 1, 2019): 3218–22. http://dx.doi.org/10.1166/jnn.2019.16587.

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CuO/MCM-41 catalyst was synthesized by a simple method with the modification of ethylene glycol (EG) and characterized by powder X-ray diffraction (XRD), nitrogen sorption, scanning electron microscopy (SEM) and transmission electron microscope (SEM). Its catalytic performance in the hydrogenation of CO2 to methanol was also investigated. The results indicated that the as-synthesized CuO/MCM-41-EG catalyst took the properties of high dispersion, small particle size and high surface area, and then showed catalytic performance for the CO2 hydrogenation to methanol. At the optimum reaction temperature of 240 °C, the CuO/MCM-41-EG catalyst gave 15% CO2 conversion and 35% methanol selectivity.

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Marcantoni, Enrico, Roberto Cipolletti, Laura Marsili, Stefano Menichetti, Roberta Properzi, and Caterina Viglianisi. "An Efficient Catalytic Method for Regioselective Sulfenylation of Electron-Rich Aza-Aromatics at Room Temperature." European Journal of Organic Chemistry 2013, no. 1 (November 19, 2012): 132–40. http://dx.doi.org/10.1002/ejoc.201201100.

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Kowalska, E., E. Czerwosz, P. A. Dłużewski, M. Kozłowski, and J. Radomska. "Electron emissive properties of CNT films grown by catalytic method on different types of substrates." Diamond and Related Materials 13, no. 4-8 (April 2004): 1008–11. http://dx.doi.org/10.1016/j.diamond.2004.01.004.

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Chu, De Qing, Yun Na Dong, Zhi Ri Yu, Liang Ci Su, and Li Min Wang. "Preparation, Characterization and Catalytic Properties of the Different Types of Nanometer Crystal Manganese Dioxide." Advanced Materials Research 287-290 (July 2011): 708–11. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.708.

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The different types of nanometer crystal manganese dioxides was prepared by hydrothermal method, and was characterized by scanning electron microscopy and X-ray diffraction. Meanwhile, the catalytic properties of the samples were investigated in catalytic degradation of methylene blue. The results showed that the different types of nano-crystal manganese dioxide had uniform crastallinity and good dispersion. And the degradation rate of methylene blue has reached more than 60%.

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Zhang, Xiying, Xiaohua Liu, Jianlin Zhang, Dong Zhang, Lili Lin, and Xiaoming Feng. "Enantioselective [3 + 2] cycloaddition and rearrangement of thiazolium salts to synthesize thiazole and 1,4-thiazine derivatives." Organic Chemistry Frontiers 5, no. 13 (2018): 2126–31. http://dx.doi.org/10.1039/c8qo00370j.

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A highly efficient catalytic asymmetric [3 + 2] cycloaddition/rearrangement cascade of thiazolium N-ylides with various electron-deficient 2-π components was achieved, providing a convenient method to access hydropyrrolo-thiazole and hydropyrrolo-thiazine derivatives.

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Journal articles on the topic 'Electron-catalytic method'

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