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Articles 1 - 27 of 27
Full-Text Articles in Physical Sciences and Mathematics
Advances In Research On Hydrogenation Saturation Of Polycyclic Aromatic Hydrocarbons In Coal Tar, He Xinfu, Gao Fan, Wu Hongju, Zhang Xiaoqin, Ma Tao, Shi Zhiwei, Zhou Anning, Zhang Yating
Advances In Research On Hydrogenation Saturation Of Polycyclic Aromatic Hydrocarbons In Coal Tar, He Xinfu, Gao Fan, Wu Hongju, Zhang Xiaoqin, Ma Tao, Shi Zhiwei, Zhou Anning, Zhang Yating
Coal Geology & Exploration
Significance Polycyclic aromatic hydrocarbons (PAHs), a predominant component in coal tar, can be used to produce jet fuels with high energy density and thermal stability through hydrogenation saturation. Based on the characteristics of the PAH hydrogenation process, this study proposed that primary challenges in PAH hydrogenation saturation include the resonance energy of PAHs themselves, the spatial site resistance of hydrogenation intermediates, and the competitive adsorption of feedstocks and intermediates on active sites in the catalysts. Progress Based on the review of research progress in catalysts for PAH hydrogenation saturation in recent years, this study analyzed the substantial factor influencing the …
Synthesis And Characterization Of Renewable Heterogeneous Catalyst Zno Supported Biogenic Silica From Pineapple Leaves Ash For Sustainable Biodiesel Conversion, Nadila Pratiwi, Suriati Eka Putri, Yulia Shinta, Arya Ibnu Batara, Diana Eka Pratiwi, Abd Rahman, Nur Ahmad, Heryanto Heryanto
Synthesis And Characterization Of Renewable Heterogeneous Catalyst Zno Supported Biogenic Silica From Pineapple Leaves Ash For Sustainable Biodiesel Conversion, Nadila Pratiwi, Suriati Eka Putri, Yulia Shinta, Arya Ibnu Batara, Diana Eka Pratiwi, Abd Rahman, Nur Ahmad, Heryanto Heryanto
Karbala International Journal of Modern Science
This study reports on the first case of the low-cost and environmentally friendly ZnO/SiO2 heterogeneous catalyst from pineapple leaves ash (PLA). Catalyst shows excellent performance in catalyzing the transesterification of waste cooking oil (WCO) with methanol for biodiesel conversion. This study focuses on assessing the influence of Zn content on physicochemical characteristics, using XRD, FTIR, SEM, and N2 adsorption-desorption methods. In addition, three different Zn content levels (20, 25, and 30 %wt) were applied. The results showed that all ZnO/SiO2 samples exhibited characteristics suitable for use as catalyst with an average crystallite size of 31.83-34.15 nm, and a surface area …
Intercalation Of Pyrazolone-Based Oxalamide Metal Complexes Into Na-Montmorillonite For Catalytic Liquid-Phase Oxidation Of Phenol Using H2o2, Serhat Uzan, Eyüp Başaran
Intercalation Of Pyrazolone-Based Oxalamide Metal Complexes Into Na-Montmorillonite For Catalytic Liquid-Phase Oxidation Of Phenol Using H2o2, Serhat Uzan, Eyüp Başaran
Turkish Journal of Chemistry
The intercalation of pyrazolone-based oxalamide metal complexes into Na-montmorillonite (Na-MMT) for catalytic liquid-phase oxidation of phenol using H2O2 was undertaken by a flexible ligand method using metal ions including Mn(II), Zn(II), and Sn(II). First, the metal ions were exchanged with the sodium ions of Na-MMT, and then these metal ions were complexed with a new pyrazolone-based oxalamide ligand. The intercalated metal complexes were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, elemental analysis, and thermogravimetric analysis. Phenol was successfully oxidized by heterogeneous catalysts based on Mn(II), Zn(II), and Sn(II) pyrazolone-based oxalamide complexes intercalated into …
Catalytic Evaluation Of Cellulose Pyrolysis By Using Nanosized Metal Oxide Catalysts, Yusuf Osman Donar, Ali̇ Tolga Ünalan, Samed Ergenekon, Ali̇ Sinağ
Catalytic Evaluation Of Cellulose Pyrolysis By Using Nanosized Metal Oxide Catalysts, Yusuf Osman Donar, Ali̇ Tolga Ünalan, Samed Ergenekon, Ali̇ Sinağ
Turkish Journal of Chemistry
In this study, effects of TiO$_{2}$ and ZnO nanometal oxides on cellulose pyrolysis have been investigated. Both catalysts have been synthesized via hydrothermal method and characterized by using different techniques. Catalytic and catalyst-free experiments were carried out so as to identify the catalytic abilities of synthesized nanoparticles. Catalyst-free experiments were carried out at 500, 600, and 700 °C in order to determine the optimal condition for pyrolysis and it was found as 700 °C. Optimum catalyst ratio for cellulose pyrolysis was found as 5% (w/w) for both TiO$_{2}$ and ZnO catalysts. GC-MS and micro-GC analyses were conducted in order to …
Electrocatalytic “Volcano-Type” Effect Of Nano-Tio2 (A)/(R) Phase Content In Pt/Tio2-CnX Catalyst, Ai-Lin Cui, Yang Bai, Hong-Ying Yu, Hui-Min Meng
Electrocatalytic “Volcano-Type” Effect Of Nano-Tio2 (A)/(R) Phase Content In Pt/Tio2-CnX Catalyst, Ai-Lin Cui, Yang Bai, Hong-Ying Yu, Hui-Min Meng
Journal of Electrochemistry
The relationship between the electrochemical activity of fuel cell catalysts and Pt particle size, as well as the catalyst support and co-catalyst is still unclear. In this work, FESEM, XRD, BET, TEM and CV techniques were adopted to investigate the effects of TiO2 anatase (A)/rutile (R) phases content on the electrochemical activity of Pt electrocatalyst. The results showed that the anatase-rutile phase transformation occurred during the heat treatment of TiO2 at 700 ~ 900 oC accompanied by the growth of two-phase crystalline size, and anatase was completely transformed into rutile at 900 oC. TEM results revealed that the …
The Relation Between Surface Acidity And Moo3:Al2o3 Ratio On The Ternary Mixed Oxide Catalysts For The Conversion Of Propan-2-Ol, Hani Zeidan, Ebru Erünal, Mustafa Esen Marti
The Relation Between Surface Acidity And Moo3:Al2o3 Ratio On The Ternary Mixed Oxide Catalysts For The Conversion Of Propan-2-Ol, Hani Zeidan, Ebru Erünal, Mustafa Esen Marti
Turkish Journal of Chemistry
In this study, ternary mixed oxide catalysts containing Al2O3-MoO3-MgO and Al2O3-MoO3-WO3 were prepared with a changing ratio of MoO3:Al2O3 between 0.05 and 20.00. All catalysts showed 100% selectivity towards propene during the conversion of propan-2-ol at temperatures between 220 and 400 °C. The catalysts prepared from WO3 possessed very strong acid sites, which cause higher catalytic activity than catalysts prepared from MgO. Besides, the ratio of MoO3:Al2O3 was found to be directly proportional to the conversion …
Fabrication And Characterization Of Amidoxime-Functionalized Silica Decorated Withcopper: A Catalytic Assembly For Rapid Reduction Of Dyes, Ijaz Ahmed Khan, Muhammad Inaam-Ul-Hassan, Hazrat Hussain, Syed Mujtaba Shah, Tariq Yasin
Fabrication And Characterization Of Amidoxime-Functionalized Silica Decorated Withcopper: A Catalytic Assembly For Rapid Reduction Of Dyes, Ijaz Ahmed Khan, Muhammad Inaam-Ul-Hassan, Hazrat Hussain, Syed Mujtaba Shah, Tariq Yasin
Turkish Journal of Chemistry
In this study, amidoxime-functionalized silica decorated with copper (AFS-Cu) was fabricated and tested for its catalytic application. Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction were employed to characterize its structure and morphology. The application of AFS-Cu as a catalyst for the catalytic reduction of methylene blue (MB) in aqueous media using NaBH$_{4}$ as reductant was evaluated. The ability to reuse as well as the effect of catalyst dose and pH of solution on the catalytic activity was investigated. The reduction of MB followed pseudo-first-order kinetics and the rate constant (k) was 0.6224 min$^{-1}$. …
Nio@Rgo Supported Palladium And Silver Nanoparticles As Electrocatalysts For Oxygen Reduction Reaction, Shuo Yao, Tai-Zhong Huang, Rizwan Haider, Heng-Yi Fang, Jie-Mei Yu, Zhan-Kun Jiang, Dong Liang, Yue Sun, Xian-Xia Yuan
Nio@Rgo Supported Palladium And Silver Nanoparticles As Electrocatalysts For Oxygen Reduction Reaction, Shuo Yao, Tai-Zhong Huang, Rizwan Haider, Heng-Yi Fang, Jie-Mei Yu, Zhan-Kun Jiang, Dong Liang, Yue Sun, Xian-Xia Yuan
Journal of Electrochemistry
For pervasive applications of fuel cells, highly efficient and economical materials are required to replace Pt-based catalysts for oxygen reduction reaction (ORR). In this study, the NiO@rGO, Pd-NiO@rGO and Ag-NiO@rGO nanoparticles were synthesized, and their catalytic performances toward ORR were investigated. The results revealed that all the three materials were capable of catalyzing ORR, but both the Pd-NiO@rGO and Ag-NiO@rGO showed the better performances compared with the NiO@rGO in terms of the reaction pathway being 4-electron process, the increases of the onset potential and the intermediate yielding rate, as well as the extended stability. Moreover, the effect of Pd modification …
Preparation Of Different Thin Film Catalysts By Direct Current Magnetron Sputtering Forhydrogen Generation, Gamze Bozkurt, Abdulkadi̇r Özer, Ayşe Bayrakçeken Yurtcan
Preparation Of Different Thin Film Catalysts By Direct Current Magnetron Sputtering Forhydrogen Generation, Gamze Bozkurt, Abdulkadi̇r Özer, Ayşe Bayrakçeken Yurtcan
Turkish Journal of Chemistry
In this study, thin films of Co, Ni, Pd, and Pt were prepared on Co$_{3}$O$_{4}$ support material in pellet form using the direct current (DC) magnetron sputtering method for use as catalysts for hydrogen generation from NaBH4.Characterization of the catalysts was carried out using X-ray diffraction (XRD), scanning electronic microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). According to cross-sectional SEM images, catalyst thicknesses were observed in the range of approximately 115.3-495.8 nm. The particle sizes were approximately 25.0, 21.4, 33.9, and 9.5 nm for Ni-Co$_{3}$O$_{4}$, Co-Co$_{3}$O$_{4}$, Pd-Co$_{3}$O$_{4}$, and Pt-Co$_{3}$O$_{4}$ catalysts, respectively. The increase in NaOH initial concentration provides an increase …
Influences Of Morphology And Nitrogen Doping On The Electrocatalytic Characteristics For Oxygen Reduction Reaction Of Nio/Rgo, Dong Liang, Heng-Yi Fang, Shuo Yao, Jie-Mei Yu, Zhao-Liang Zhang, Zhan-Kun Jiang, Xue-Ping Gao, Tai-Zhong Huang
Influences Of Morphology And Nitrogen Doping On The Electrocatalytic Characteristics For Oxygen Reduction Reaction Of Nio/Rgo, Dong Liang, Heng-Yi Fang, Shuo Yao, Jie-Mei Yu, Zhao-Liang Zhang, Zhan-Kun Jiang, Xue-Ping Gao, Tai-Zhong Huang
Journal of Electrochemistry
In this research, the reduced graphene oxide (rGO) supported sheet-like NiO (NiO/rGO) and spherical-like NiO (NiO/N-rGO) catalysts for oxygen reduction reaction (ORR) were prepared. The structures, morphologies and chemical states of the two catalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical catalytic performance of the two catalysts for ORR were investigated by cyclic voltammetry (CV), Tafel, linear sweeping voltammetry (LSV), rotating disc electrode (RDE) and rotating ring disc electrode (RRDE) tests. Electrochemical results showed that the current density and onset potential (about 0.89 V) …
Cyclic Peptide Catalyst Design, Millicent Campbell, David Michaelis
Cyclic Peptide Catalyst Design, Millicent Campbell, David Michaelis
Journal of Undergraduate Research
Enzymes found in nature are more efficient catalysts than those used in organic chemistry labs. However, natural enzymes are not ideal for organic synthesis because they only make one product and only work in specific conditions. The Michaelis lab designed a catalyst capable of mimicking enzyme-like reactivity in the lab. This catalyst consists of an alpha helix with an imidazolidinone catalyst and a thiourea catalyst (see figure 1). The imidazolidinone catalyst and thiourea catalysts are attached adjacent to each other on the alpha helix, which acts as a rigid scaffold that can mimic the proximity effects seen in natural enzymes. …
The Catalytic Effects Of In Situ Prepared N-Heterocyclic Carbenes From Benzimidazole Salts In Suzuki--Miyaura Cross-Coupling Reaction And Uses In Catalytic Preparation Of 1,3,5-Triphenyl-1,3,5-Triazinane-2,4,6-Trione From Phenyl Isocyanate, Ülkü Yilmaz, Hasan Küçükbay
The Catalytic Effects Of In Situ Prepared N-Heterocyclic Carbenes From Benzimidazole Salts In Suzuki--Miyaura Cross-Coupling Reaction And Uses In Catalytic Preparation Of 1,3,5-Triphenyl-1,3,5-Triazinane-2,4,6-Trione From Phenyl Isocyanate, Ülkü Yilmaz, Hasan Küçükbay
Turkish Journal of Chemistry
Many benzimidazole salts bearing a 3-phenylpropyl substituent (1a-1h) were synthesized and their structures were identified by $^{1}$H NMR, $^{13}$C NMR, and IR spectroscopic methods and elemental analysis. These N-heterocyclic carbene (NHC) precursors were used as a part of a catalytic system including Pd(OAc)$_{2}$ and the base in the Suzuki--Miyaura cross-coupling reaction under microwave irradiation. They were also used as catalysts in the cyclotrimerization of phenyl isocyanate to yield 1,3,5-triphenyl-1,3,5-triazinane-2,4,6-trione. It has been observed that benzimidazole salts made a positive contribution to both catalytic reactions as a NHC precursor.
Nanocomposite Copper Metal As An Efficient Heterogeneous Catalyst In Click Synthesis Of 1,2,3-Triazoles In Aqueous Media, Vajihe Nejadshafiee, Hossein Naeimi
Nanocomposite Copper Metal As An Efficient Heterogeneous Catalyst In Click Synthesis Of 1,2,3-Triazoles In Aqueous Media, Vajihe Nejadshafiee, Hossein Naeimi
Turkish Journal of Chemistry
Copper/periodic mesoporous organosilica (Cu/PMO) nanocomposites provided a highly active, reusable, globular, solid-phase catalyst for click chemistry. The reaction proceeds by mixing organohalides, sodium azide, alkyne, and the catalyst in an aqueous medium to afford the desired products. The cost efficiency and recyclability of the catalyst up to six runs without appreciable loss of activity and high yields of products make this procedure greener.
Recycling Mf Solid Waste Into Mesoporous Nitrogen-Doped Carbon With Iron Carbide Complex In Graphitic Layers As An Efficient Catalyst For Oxygen Reduction Reaction, Can-Yun Zhao, Lin Huang, Yong You, Ying-Fang Yao, Xiao-Gang Su, Hong Wan, Jian-Guo Liu, Cong-Ping Wu
Recycling Mf Solid Waste Into Mesoporous Nitrogen-Doped Carbon With Iron Carbide Complex In Graphitic Layers As An Efficient Catalyst For Oxygen Reduction Reaction, Can-Yun Zhao, Lin Huang, Yong You, Ying-Fang Yao, Xiao-Gang Su, Hong Wan, Jian-Guo Liu, Cong-Ping Wu
Journal of Electrochemistry
Nitrogen-doped carbon materials with iron ions are known as catalytic growth agents for the oxygen reduction reaction (ORR) in fuel cells, but the design and synthesis of high-performance and low-cost catalysts still remain a significant challenge. Herein, we present a cost-effective approach to dispose of MF solid waste as the precursor for the synthesis of MCFes catalyst with the favorable structure features such as the high specific surface area, abundant active sites and suitable pore structure. The results showed that the MCFe-10/10/2 had specific surface area as high as 780.7 m2•g-1 and high efficient catalytic activity comparable …
Ag(I) Complexes Of Benzimidazol-2-Ylidene Ligands: A Study Of Catalytic Efficiency Towards Three-Component Coupling Reactions, Rafet Kilinçarslan, Nai̇m Sadiç, Beki̇r Çeti̇nkaya
Ag(I) Complexes Of Benzimidazol-2-Ylidene Ligands: A Study Of Catalytic Efficiency Towards Three-Component Coupling Reactions, Rafet Kilinçarslan, Nai̇m Sadiç, Beki̇r Çeti̇nkaya
Turkish Journal of Chemistry
The $N$-heterocyclic carbene (NHC)--Ag(I) complexes 3a-c were synthesized from benzimidazolium chlorides (2a-c = NHC.HCl), incorporating benzyl derivatives and a 2-methoxyethyl group (a: $^{3}$N = 2,4,6-trimethylbenzyl; b: $^{3}$N = 2,3,5,6-tetramethylbenzyl; c: $^{3}$N = pentamethylbenzyl). The compounds were characterized by spectroscopic and elemental analyses. The synthesized NHC-Ag(I) complexes (3a-c) were tested as catalysts for the catalytic three-component coupling reaction of aldehyde, alkyne, and amine to propargylamines in various solvents. All complexes were active catalysts for catalytic three-component coupling reactions with good yields under neat and mild conditions (after 4 h, yields of up to 94%).
Efficient C--C Cross-Coupling Reactions By (Isatin)-Schiff Base Functionalized Magnetic Nanoparticle-Supported Cu(Ii) Acetate As A Magnetically Recoverable Catalyst, Seyedeh Simin Miri, Mehdi Khoobi, Fatemeh Ashouri, Farnaz Jafarpour, Parviz Rashidi Ranjbar, Abbas Shafiee
Efficient C--C Cross-Coupling Reactions By (Isatin)-Schiff Base Functionalized Magnetic Nanoparticle-Supported Cu(Ii) Acetate As A Magnetically Recoverable Catalyst, Seyedeh Simin Miri, Mehdi Khoobi, Fatemeh Ashouri, Farnaz Jafarpour, Parviz Rashidi Ranjbar, Abbas Shafiee
Turkish Journal of Chemistry
Copper catalysts were simply fabricated through surface modification of superparamagnetic iron nanoparticles with indoline-2,3-dione(isatin)-Schiff-base and interaction with Cu from low-cost commercially available starting materials. Catalysts were characterized using atomic absorption spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, UV/Vis spectroscopy, scanning electron microscopy, and transmission electron microscopy. These catalysts showed high efficiency for phosphine-free Mizoroki--Heck and Suzuki--Miyaura cross-coupling reactions with good diversity and generality. The catalysts could be easily recovered and reused several times without a significant loss in their catalytic activity and stability.
Enhanced Electrocatalytic Efficiency Of C/Mwnts For Methanol Oxidation Using Ni Deposited On Mwnts, Murat Farsak, Gülfeza Kardaş
Enhanced Electrocatalytic Efficiency Of C/Mwnts For Methanol Oxidation Using Ni Deposited On Mwnts, Murat Farsak, Gülfeza Kardaş
Turkish Journal of Chemistry
The power density of direct methanol fuel cells (DMFCs) can be changed by using different anode materials. Especially porous materials are preferred for the anode. In the present study, multiwall carbon nanotubes were first injected into graphite. Then, by depositing nickel, a catalyst was prepared for use as the anode material of the DMFC. This catalyst was named Ni@MWNTs. The oxidation of methanol and some kinetic parameters were investigated in KOH solution. Cyclic voltammetry was used for the electrochemical measurements. Kinetic parameters of the methanol oxidation were determined at different temperatures, scan rates, and concentrations of methanol. The surface morphologies …
Resorcinarene-Mono-Benzimidazolium Salts As Nhc Ligands For Suzuki--Miyaura Cross-Couplings Catalysts, Ümi̇t İşci̇, Muhi̇tti̇n Aygün, Resul Sevi̇ncek, Yunus Zorlu, Fabienne Dumoulin
Resorcinarene-Mono-Benzimidazolium Salts As Nhc Ligands For Suzuki--Miyaura Cross-Couplings Catalysts, Ümi̇t İşci̇, Muhi̇tti̇n Aygün, Resul Sevi̇ncek, Yunus Zorlu, Fabienne Dumoulin
Turkish Journal of Chemistry
Two mono-benzimidazolium salts of resorcinarene have been prepared and used as ligands in Suzuki--Miyaura cross-coupling reactions. They have been fully characterized by $^{1}$H and $^{13}$C NMR, MALDI, and FT-IR spectroscopic methods, and their structures were confirmed by X-ray diffraction analysis. These two new resorcinarene-based mono-benzimidazolium salts showed good catalytic activity for coupling reactions in DMF. The highest conversion was achieved for arylation of 4-bromotoluene using the resorcinarenyl mono-dimethylbenzimidazolium salt.
The Synthesis Of 1,3-Dialkyl-4-Methylimidazolinium Salts And Their Application In Palladium Catalyzed Heck Coupling Reactions, Murat Yi̇ği̇t, Güli̇n Bayam, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r
The Synthesis Of 1,3-Dialkyl-4-Methylimidazolinium Salts And Their Application In Palladium Catalyzed Heck Coupling Reactions, Murat Yi̇ği̇t, Güli̇n Bayam, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r
Turkish Journal of Chemistry
Seven novel 1,3-dialkyl-4-methylimidazolinium chloride salts 3a--g were prepared as precursors of N-heterocyclic carbenes by reacting N,N'-alkyl-1,2-diaminopropane, triethyl orthoformate, and ammonium chloride. The salts were characterized spectroscopically. The in situ prepared palladium complexes derived from the imidazolinium salts and palladium acetate were used as catalyst in Heck coupling reactions between aryl bromides and styrene. The corresponding Heck products were obtained in good yields.
Oxidation Of Hydrocarbons With Tetra-N-Butylammonium Peroxy Monosulfate Catalyzed By \Beta-Tetrabromo-Meso-Tetrakis(4-Methoxyphenyl)- And \Beta-Tetrabromo-Meso-Tetraphenylporphyrinatomanganese(Iii), Saeed Rayati, Saeed Zakavi, Hossein Valinejad
Oxidation Of Hydrocarbons With Tetra-N-Butylammonium Peroxy Monosulfate Catalyzed By \Beta-Tetrabromo-Meso-Tetrakis(4-Methoxyphenyl)- And \Beta-Tetrabromo-Meso-Tetraphenylporphyrinatomanganese(Iii), Saeed Rayati, Saeed Zakavi, Hossein Valinejad
Turkish Journal of Chemistry
\beta-Tetrabromo-meso-tetrakis(4-methoxyphenyl)porphyrin, H_2T(4-OCH_3P)PBr_4, was synthesized and characterized by UV-Vis and ^1H NMR spectroscopy. Oxidation of alkanes and olefins with tetra-n-butylammonium peroxymonosulfate (n-Bu_4NHSO_5) was studied in the presence of MnT(4-OCH_3P)PBr_4(OAc) and MnTPPPBr_4(OAc) (TPP = meso-tetraphenylporphyrin). While significance differences were observed between the catalytic activities of the title complexes in the oxidation of alkanes, the 2 manganese porphyrins showed comparable activities in oxidation of most of the olefins used. However, the latter showed greater catalytic performance in the oxidation of the hydrocarbons. Moreover, the oxidative degradation of the former (60 %) was greater than that of the latter (45 %) in the oxidation …
Comparison Of Catalytic Performance On Different Materials Supported Pd Catalysts For Formic Acid Oxidation, Su-Dong Yang, Yan-Yu Liang, Zhu-Liang Wen, Qi-Jun Song, Xiao-Gang Zhang
Comparison Of Catalytic Performance On Different Materials Supported Pd Catalysts For Formic Acid Oxidation, Su-Dong Yang, Yan-Yu Liang, Zhu-Liang Wen, Qi-Jun Song, Xiao-Gang Zhang
Journal of Electrochemistry
Graphite oxide (GO) was prepared from by Hummers method. Then the graphene nanosheets supporting Pd catalysts were prepared by a single-step chemical reduction method. The electrocatalytic performance for formic acid oxidation of the prepared Pd/graphene composite was studied as an electrode material in comparison with the composite catalysts based on the other carbons (MWCNTs, SWCNTs, and Vulcan XC-72 carbon black). X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements indicated that the Pd nanoparticles were well dispersed on the surface of the graphene nanosheets with a small particle size. The electrocatalytic oxidation of formic acid was studied by electrochemically active …
Preparation And Electrocatalytic Activity Of The Pt/Wc/Tio2 Composites, Chun-An Ma, Bin Yu, Mei-Qin Shi, Xiao-Ling Lang
Preparation And Electrocatalytic Activity Of The Pt/Wc/Tio2 Composites, Chun-An Ma, Bin Yu, Mei-Qin Shi, Xiao-Ling Lang
Journal of Electrochemistry
TiO2 was used as the support for preparation of Pt/WC/TiO2 composite catalyst. The composites were characterized by XRD, SEM and TEM methods. The electrocatalytical activity of Pt/WC/TiO2 composite for oxidation of methanol was investigated by cyclic voltammetry. Pt/WC/TiO2 exhibited higher activity compared with that of Pt/TiO2 and Pt/WC composite catalysts. Based on this we discussed the effects of crystal phases of TiO2 on the electrocatalytical activity of Pt/WC/TiO2 composite catalyst.
Electrocatalytic Oxidation Of Ethanol On Various Metal Ad-Layer Modified Au(111) Electrodes In Alkaline Solution, Zekerya Dursun, Şükri̇ye Ulubay Karabi̇beroğlu, Buket Gelmez, Aydan Başaran
Electrocatalytic Oxidation Of Ethanol On Various Metal Ad-Layer Modified Au(111) Electrodes In Alkaline Solution, Zekerya Dursun, Şükri̇ye Ulubay Karabi̇beroğlu, Buket Gelmez, Aydan Başaran
Turkish Journal of Chemistry
Ethanol oxidation was studied on single-crystal Au(111) electrodes that were modified by platinum, palladium, and cadmium metal ad-layers. The metal ad-layer modification was carried out by the underpotential deposition process, in which controlled amounts of Pt, Pd, and Cd were electrodeposited onto the substrate as submonolayer or monolayer coverage. The activity of the metal ad-layer modified Au(111) electrodes toward ethanol oxidation was studied in alkaline media, and recorded voltammograms were compared to those of bare single crystal Au(111) and polycrystalline gold and platinum disk electrodes. In terms of the desired shift in reduction potential and increased current density, the best …
An Efficient Synthesis Of Schiff Bases Containing Benzimidazole Moiety Catalyzed By Transition Metal Nitrates, Akbar Mobinikhaledi, Naser Foroughifar, Mehdi Kalhor
An Efficient Synthesis Of Schiff Bases Containing Benzimidazole Moiety Catalyzed By Transition Metal Nitrates, Akbar Mobinikhaledi, Naser Foroughifar, Mehdi Kalhor
Turkish Journal of Chemistry
A simple and efficient method has been developed for the synthesis of some novel Schiff bases via the reaction of aromatic aldehydes with 2-aminobenzimidazole by using catalytic amount of M(NO_3)_2.xH_2O in an organic solvent at room temperature. Some advantages of this protocol are its very good yields, use of available catalysts, simple workup procedure, and short reaction times.
Oxygen Enrichment Effect Of Mno_2-Pt/C Compound Catalyst To The Cathode Of Pemfc, Hong-Feng Xu, Mao-Feng Zhang, Quan-Quan Gan, Cai-Sheng Huang
Oxygen Enrichment Effect Of Mno_2-Pt/C Compound Catalyst To The Cathode Of Pemfc, Hong-Feng Xu, Mao-Feng Zhang, Quan-Quan Gan, Cai-Sheng Huang
Journal of Electrochemistry
TO study of the oxygen storage material of air cathode is crucial for increasing performance of proton exchange membrane fuel cell.Using the MnO2 as oxygen storage materials,a MnO2-Pt/C catalysts were prepared and is used to replace the conventional Pt/C in air cathode.The electrochemical performance of air cathode composed of MnO2 supported on Pt/C and the properties of fuel cell composed of MnO2-Pt/C were investigated by using the CV,galvanostatic dischange method and TEM.
Investigation On The Resistance To Electrochemical Oxidation Of Carbon Nanotubes With Various Diameters, Yu-Yan Shao, Ge-Ping Yin, Yun-Zhi Gao, Peng-Fei Shi
Investigation On The Resistance To Electrochemical Oxidation Of Carbon Nanotubes With Various Diameters, Yu-Yan Shao, Ge-Ping Yin, Yun-Zhi Gao, Peng-Fei Shi
Journal of Electrochemistry
The resistance to electrochemical oxidation of multi-wall carbon nanotubes(CNT) with various diameters is investigated by applying a fixed potential of 1.2 V(RHE) for 120 h in 0.5 mol L~(-1) H_(2)SO_(4).The oxidation current of CNTs decreases with their diameters,but CNTs between 10~20 nm in diameter(D1020) shows the lowest oxidation current.XPS analysis shows that,after oxidation,the increase in surface oxygen for D1020 is the smallest,implying that the oxidation degree for D1020 is the lowest.The conclusion can be reached that CNTs between 10~20 nm in diameter are the most resistant to electrochemical oxidation.The difference in electrochemical stability of CNTs is attributed to the difference …
Oxygen Enrichment Effect Of Ceo_2 To The Cathode Performance Of Proton Exchange Membrane Fuel Cell, Xiang-Li Hou, Hong-Feng Xu, Jian-Hua Dong, Xin Sun
Oxygen Enrichment Effect Of Ceo_2 To The Cathode Performance Of Proton Exchange Membrane Fuel Cell, Xiang-Li Hou, Hong-Feng Xu, Jian-Hua Dong, Xin Sun
Journal of Electrochemistry
CeO_2 was added to Pt/C catalyst in the cathode of PEMFC by both sol and impregnation methods.The samples were evaluated by TEM,cyclic voltammogram techniques and proton exchange membrane fuel cell performance test.The addition of CeO_2 obviously improved the performance of PEMFC and represented a notable function of oxygen enrichment in the cathode side.But with the addition of CeO_2,part of the catalyst surface was covered and led to the performance drop of the PEMFC.The best content of CeO_2 is 1% when it is added by impregnation method and 3% when it is added by sol method.