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Lin Zhuang - One of the best experts on this subject based on the ideXlab platform.
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exploring the composition activity relation of ni cu binary alloy electrocatalysts for hydrogen Oxidation Reaction in alkaline media
ACS Applied Energy Materials, 2019Co-Authors: Gongwei Wang, Li Xiao, Bing Huang, Lin ZhuangAbstract:The development of nonprecious electrocatalysts for hydrogen Oxidation Reaction (HOR) in alkaline is becoming one of the major obstacles to alkaline polymer electrolyte fuel cells (APEFCs). In this work, a series of Ni–Cu binary alloy films are high-throughput prepared using a combinatorial magnetron cosputtering method, and their corresponding electrocatalytic performances toward HOR in alkaline media are systematically studied. Both the intrinsic activity and antiOxidation property of Ni are remarkably enhanced after Cu doping. A volcano-type relation between HOR activity and Cu doping content is revealed. The maximum activity is found at ca. 40 at. % Cu, with the exchange current density 4 times higher than that of pure Ni. This study gives us a deeper understanding of the impact of Cu addition on the HOR catalytic activity of Ni.
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Unraveling the composition-activity relationship of PtRu binary alloy for hydrogen Oxidation Reaction in alkaline media
Journal of Power Sources, 2019Co-Authors: Gongwei Wang, Li Xiao, Bing Huang, Lin ZhuangAbstract:Abstract The research and development of hydrogen Oxidation Reaction catalysts in alkaline media is a prerequisite for the commercialization of alkaline polymer electrolyte fuel cell. Pt Ru bimetallic catalyst was found to be more active towards HOR than Pt in alkaline, but the composition-activity relationship of Pt Ru alloys is still lacking. Herein, a series of Pt Ru alloy planar electrodes with 14 different compositions were prepared in a high-throughput fashion using an improved magnetron sputtering method. The atomic ratio of Pt was controlled from 6.7% to 99.7% within the samples. The corresponding electro-catalytic activities towards the HOR in alkaline were systematically measured by rotating disc electrode method. A volcano-shape relationship between the HOR exchange current density and the Ru atomic fraction was revealed, and maximum activity was observed at ca. 55% content of Ru. The enhancement in electro-catalytic activity is attributed to a reduction in the electronic charge density of Pt upon Ru doping.
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Exploring the Composition–Activity Relation of Ni–Cu Binary Alloy Electrocatalysts for Hydrogen Oxidation Reaction in Alkaline Media
2019Co-Authors: Gongwei Wang, Li Xiao, Bing Huang, Lin ZhuangAbstract:The development of nonprecious electrocatalysts for hydrogen Oxidation Reaction (HOR) in alkaline is becoming one of the major obstacles to alkaline polymer electrolyte fuel cells (APEFCs). In this work, a series of Ni–Cu binary alloy films are high-throughput prepared using a combinatorial magnetron cosputtering method, and their corresponding electrocatalytic performances toward HOR in alkaline media are systematically studied. Both the intrinsic activity and antiOxidation property of Ni are remarkably enhanced after Cu doping. A volcano-type relation between HOR activity and Cu doping content is revealed. The maximum activity is found at ca. 40 at. % Cu, with the exchange current density 4 times higher than that of pure Ni. This study gives us a deeper understanding of the impact of Cu addition on the HOR catalytic activity of Ni
Dewei Yao - One of the best experts on this subject based on the ideXlab platform.
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a novel ir ceo2 c nanoparticle electrocatalyst for the hydrogen Oxidation Reaction of alkaline anion exchange membrane fuel cells
RSC Advances, 2017Co-Authors: Jun Chi, Jia Jia, Xueqiang Gao, Bowen Qin, Dewei YaoAbstract:Alkaline anion exchange membrane fuel cells have faster kinetics for the oxygen reduction Reaction (ORR) than proton exchange membrane fuel cells; however, the hydrogen Oxidation Reaction (HOR) at anodes with precious metals is more sluggish under alkaline conditions than that under acidic conditions, which hinders the further development of fuel cells. Herein, a novel catalyst, iridium nanoparticle-supported ceria–carbon black (10% Ir/CeO2–C), was developed for use in the hydrogen Oxidation Reaction (HOR) under basic conditions. Cyclic voltammetry reveals that the electrochemical surface area of 10% Ir/CeO2–C is 1.5 times that of 10% Ir/C. The RDE measurement suggests that the exchange current density of 10% Ir/CeO2–C is 2.4 times that of 10% Ir/C, and the mass activity and specific activity of 10% Ir/CeO2–C for HOR are greater than those of 10% Ir/C by 2.8 fold and 1.8 fold, respectively. The effective prevention of the agglomeration of the highly dispersed Ir nanoparticles could be ascribed to the strong metal–support interaction between Ir and CeO2, and the promoted electrocatalytic activity would benefit from the oxophilic effect due to the higher oxygen storage-release capacity of ceria. Thus, 10% Ir/CeO2–C would be a good candidate for use at the anode of alkaline anion exchange membrane fuel cells.
Juan M. Feliu - One of the best experts on this subject based on the ideXlab platform.
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pt richcore sn richsubsurface ptskin nanocubes as highly active and stable electrocatalysts for the ethanol Oxidation Reaction
Journal of the American Chemical Society, 2018Co-Authors: Ruben Rizo, Juan M. Feliu, Rosa M Aranais, Elliot Padgett, David A Muller, M J Lazaro, Jose Sollagullon, E Pastor, Hector D AbrunaAbstract:Direct ethanol fuel cells are one of the most promising electrochemical energy conversion devices for portable, mobile and stationary power applications. However, more efficient and stable and less expensive electrocatalysts are still required. Interestingly, the electrochemical performance of the electrocatalysts toward the ethanol Oxidation Reaction can be remarkably enhanced by exploiting the benefits of structural and compositional sensitivity and control. Here, we describe the synthesis, characterization, and electrochemical behavior of cubic Pt–Sn nanoparticles. The electrochemical activity of the cubic Pt–Sn nanoparticles was found to be about three times higher than that obtained with unshaped Pt–Sn nanoparticles and six times higher than that of Pt nanocubes. In addition, stability tests indicated the electrocatalyst preserves its morphology and remains well-dispersed on the carbon support after 5000 potential cycles, while a cubic (pure) Pt catalyst exhibited severe agglomeration of the nanopart...
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on the activation energy of the formic acid Oxidation Reaction on platinum electrodes
Journal of Electroanalytical Chemistry, 2015Co-Authors: Juan V Peralesrondon, Enrique Herrero, Juan M. FeliuAbstract:Abstract A temperature dependent study on the formic acid Oxidation Reaction has been carried out in order to determine the activation energy of this Reaction on different platinum single crystal electrodes, namely Pt(1 0 0), Pt(1 1 1), Pt(5 5 4) and Pt(5 4 4) surfaces. The chronoamperometric transients obtained with pulsed voltammetry have been analyzed to determine the current densities through the active intermediate and the CO formation rate. From the temperature dependency of those parameters, the activation energy for the direct Reaction and the CO formation step have been calculated. For the active intermediate path, the activation energy are in the range of 50–60 kJ/mol. On the other hand, a large dependence on the electrode potential is found for the activation energy of the CO formation Reaction on the Pt(1 0 0) electrode, and the activation energy values for this process range between 20 and 100 kJ/mol. These results have been explained using a Reaction mechanism in which the Oxidation of formic acid requires the presence of a pre-adsorbed anion on the electrode surface.
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effects of the anion adsorption and ph on the formic acid Oxidation Reaction on pt 111 electrodes
Electrochimica Acta, 2014Co-Authors: Juan V Peralesrondon, Enrique Herrero, Juan M. FeliuAbstract:Abstract The effects of solution pH and anion adsorption for the formic acid Oxidation Reaction on the Pt(111) electrode have been examined using electrochemical techniques. Regarding the pH effects, it has been found that Oxidation currents for this Reaction increase with pH, which indicates that solution formate is involved in the Reaction mechanism. Unexpectedly, the adsorption of sulfate on the Pt(111) electrode has a positive effect on the Oxidation of formic acid, which also suggests that adsorbed anions are also involved in the mechanism. The activation energy calculated from temperature dependent measurements diminishes with the solution pH and also in the presence of adsorbed sulfate. These measurements corroborate the involvement of solution formate and anions in the Oxidation mechanism. Using these results, a rate equation for the Oxidation of formic acid is proposed. The current values calculated from this equation are in very good agreement with the experimental currents in perchloric acid solutions.
Zhongbin Zhuang - One of the best experts on this subject based on the ideXlab platform.
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investigating the influences of the adsorbed species on catalytic activity for hydrogen Oxidation Reaction in alkaline electrolyte
Journal of the American Chemical Society, 2017Co-Authors: Siqi Lu, Zhongbin ZhuangAbstract:Catalysts for hydrogen Oxidation Reaction (HOR) in alkaline electrolyte are important for anion exchange membrane fuel cells. Understanding the role of OH– during the HOR catalytic process in alkaline electrolyte is essential to design highly active HOR catalysts. Here, we attempt to isolate the influence of OH– by using surface-controlled Pt based nanoparticles as the model catalysts. With a comparison of the HOR activity between PtNi nanoparticles and acid washed PtNi nanoparticles, which have almost the same hydrogen binding energies but much different OH binding energies, it was found that the HOR activity in alkaline electrolyte is not mainly controlled by the OH adsorption. Therefore, a bifunctional catalyst promoting OH adsorption may not useful for HOR in alkaline electrolyte. Tuning the hydrogen binding energy was found to be an efficient way to enhance the HOR activity, and making Pt base alloy is a reasonable way to tune the hydrogen binding energies.
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nickel supported on nitrogen doped carbon nanotubes as hydrogen Oxidation Reaction catalyst in alkaline electrolyte
Nature Communications, 2016Co-Authors: Stephen A Giles, Glen R Jenness, Stavros Caratzoulas, Zhongbin Zhuang, Jie Zheng, Dionisios G VlachosAbstract:The development of a low-cost, high-performance platinum-group-metal-free hydroxide exchange membrane fuel cell is hindered by the lack of a hydrogen Oxidation Reaction catalyst at the anode. Here we report that a composite catalyst, nickel nanoparticles supported on nitrogen-doped carbon nanotubes, has hydrogen Oxidation activity similar to platinum-group metals in alkaline electrolyte. Although nitrogen-doped carbon nanotubes are a very poor hydrogen Oxidation catalyst, as a support, it increases the catalytic performance of nickel nanoparticles by a factor of 33 (mass activity) or 21 (exchange current density) relative to unsupported nickel nanoparticles. Density functional theory calculations indicate that the nitrogen-doped support stabilizes the nanoparticle against reconstruction, while nitrogen located at the edge of the nanoparticle tunes local adsorption sites by affecting the d-orbitals of nickel. Owing to its high activity and low cost, our catalyst shows significant potential for use in low-cost, high-performance fuel cells.
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Non-precious metal electrocatalysts with high activity for hydrogen Oxidation Reaction in alkaline electrolytes
Energy Environ. Sci., 2014Co-Authors: Wenchao Sheng, Zhongbin Zhuang, Adam P. Bivens, Myatnoezin Myint, Robert V. Forest, Qianrong Fang, Jingguang G. Chen, Yushan YanAbstract:A ternary metallic CoNiMo catalyst is electrochemically deposited on a polycrystalline gold (Au) disk electrode using pulse voltammetry, and characterized for hydrogen Oxidation Reaction (HOR) activity by temperature-controlled rotating disk electrode measurements in 0.1 M potassium hydroxide (KOH). The catalyst exhibits the highest HOR activity among all non-precious metal catalysts (e.g., 20 fold higher than Ni). At a sufficient loading, the CoNiMo catalyst is expected to outperform Pt and thus provides a promising low cost pathway for alkaline or alkaline membrane fuel cells. Density functional theory (DFT) calculations and parallel H2-temperature programmed desorption (TPD) experiments on structurally much simpler model alloy systems show a trend that CoNiMo has a hydrogen binding energy (HBE) similar to Pt and much lower than Ni, suggesting that the formation of multi-metallic bonds modifies the HBE of Ni and is likely a significant contributing factor for the enhanced HOR activity.
Gongwei Wang - One of the best experts on this subject based on the ideXlab platform.
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exploring the composition activity relation of ni cu binary alloy electrocatalysts for hydrogen Oxidation Reaction in alkaline media
ACS Applied Energy Materials, 2019Co-Authors: Gongwei Wang, Li Xiao, Bing Huang, Lin ZhuangAbstract:The development of nonprecious electrocatalysts for hydrogen Oxidation Reaction (HOR) in alkaline is becoming one of the major obstacles to alkaline polymer electrolyte fuel cells (APEFCs). In this work, a series of Ni–Cu binary alloy films are high-throughput prepared using a combinatorial magnetron cosputtering method, and their corresponding electrocatalytic performances toward HOR in alkaline media are systematically studied. Both the intrinsic activity and antiOxidation property of Ni are remarkably enhanced after Cu doping. A volcano-type relation between HOR activity and Cu doping content is revealed. The maximum activity is found at ca. 40 at. % Cu, with the exchange current density 4 times higher than that of pure Ni. This study gives us a deeper understanding of the impact of Cu addition on the HOR catalytic activity of Ni.
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Unraveling the composition-activity relationship of PtRu binary alloy for hydrogen Oxidation Reaction in alkaline media
Journal of Power Sources, 2019Co-Authors: Gongwei Wang, Li Xiao, Bing Huang, Lin ZhuangAbstract:Abstract The research and development of hydrogen Oxidation Reaction catalysts in alkaline media is a prerequisite for the commercialization of alkaline polymer electrolyte fuel cell. Pt Ru bimetallic catalyst was found to be more active towards HOR than Pt in alkaline, but the composition-activity relationship of Pt Ru alloys is still lacking. Herein, a series of Pt Ru alloy planar electrodes with 14 different compositions were prepared in a high-throughput fashion using an improved magnetron sputtering method. The atomic ratio of Pt was controlled from 6.7% to 99.7% within the samples. The corresponding electro-catalytic activities towards the HOR in alkaline were systematically measured by rotating disc electrode method. A volcano-shape relationship between the HOR exchange current density and the Ru atomic fraction was revealed, and maximum activity was observed at ca. 55% content of Ru. The enhancement in electro-catalytic activity is attributed to a reduction in the electronic charge density of Pt upon Ru doping.
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Exploring the Composition–Activity Relation of Ni–Cu Binary Alloy Electrocatalysts for Hydrogen Oxidation Reaction in Alkaline Media
2019Co-Authors: Gongwei Wang, Li Xiao, Bing Huang, Lin ZhuangAbstract:The development of nonprecious electrocatalysts for hydrogen Oxidation Reaction (HOR) in alkaline is becoming one of the major obstacles to alkaline polymer electrolyte fuel cells (APEFCs). In this work, a series of Ni–Cu binary alloy films are high-throughput prepared using a combinatorial magnetron cosputtering method, and their corresponding electrocatalytic performances toward HOR in alkaline media are systematically studied. Both the intrinsic activity and antiOxidation property of Ni are remarkably enhanced after Cu doping. A volcano-type relation between HOR activity and Cu doping content is revealed. The maximum activity is found at ca. 40 at. % Cu, with the exchange current density 4 times higher than that of pure Ni. This study gives us a deeper understanding of the impact of Cu addition on the HOR catalytic activity of Ni
