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4,492 full-text articles. Page 68 of 139.

Palladium Adatoms On Gold Nanoparticles As Electrocatalysts For Ethanol Electro-Oxidation In Alkaline Solutions, Hui-mei CHEN, Shang-qian ZHU, Jia-le HUANG, Min-hua SHAO 2018 Department of Pharmaceutical Engineering, Zhejiang Pharmaceutical College, Ningbo 315100, Zhejiang, P.R. China;Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, P.R. China;Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering,Xiamen University, Xiamen 361005, Fujian, P.R. China.;

Palladium Adatoms On Gold Nanoparticles As Electrocatalysts For Ethanol Electro-Oxidation In Alkaline Solutions, Hui-Mei Chen, Shang-Qian Zhu, Jia-Le Huang, Min-Hua Shao

Journal of Electrochemistry

Palladium (Pd) is a good catalyst for ethanol electro-oxidation in alkaline solutions. The activity of Pd is further improved in this study by modifying the gold (Au) nanoparticles with Pd adatoms using a simple spontaneous deposition process. The Pd overlayer on the Au core (Au@Pd) is un-uniform with some Au atoms exposed to the electrolyte. The activity of Au@Pd/C toward ethanol oxidation reaction (EOR) is much higher than that of Pd/C in an alkaline solution. The peak current density of Au@Pd/C is 4.6 times higher than that of Pd/C with a 100 mV lower onset potential. The enhanced activity may …


Fuel Cells Reactor For Chemicals And Electric Energy Cogeneration, Zhi-lin HENG, Xiao-zi YUAN, Yi-mei YIN, Zi-feng MA 2018 Shanghai Electrochemical Energy Devices Research Center, Department of Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China;

Fuel Cells Reactor For Chemicals And Electric Energy Cogeneration, Zhi-Lin Heng, Xiao-Zi Yuan, Yi-Mei Yin, Zi-Feng Ma

Journal of Electrochemistry

As an energy conversion device, fuel cells can efficiently convert chemical energy into electrical energy. With the developing of technology, it is used as a reactor to conduct the synthesis of high value-added chemicals while generating electrical energy. Having benefits such as mild reaction conditions, controllability of the reaction process, high selectivity of the product, as well as high efficiency of energy utilization, it is widely used in many fields such as preparation of high value-added industrial products, gas separation, water treatment, etc. This paper introduces the current trends and statuses of fuel cell reactors in the cogeneration of chemicals …


Durability Performance Of The High-Power Fuel Cell System, Ke-yong WANG, Wei-yu SHI, Ren-fang WANG, Jia LIU, Zhong-jun HOU 2018 Sunrise Power Co., ltd./National Engineering Research Center of FC&H2 Technology, Dalian, China, 116085;

Durability Performance Of The High-Power Fuel Cell System, Ke-Yong Wang, Wei-Yu Shi, Ren-Fang Wang, Jia Liu, Zhong-Jun Hou

Journal of Electrochemistry

Fuel cell durability is the crucial challenge in fuel cell vehicle, and the lifetime of more than 5000 hours is believed to be necessary for vehicle application. Few works on durability test of the full fuel cell system have been reported. In this work, the long lifetime HySYS-30 fuel cell system was developed in Sunrise Power based on the improved MEA durability and system control strategy. The durability performance of the system was investigated under vehicle duty cycle for more than 6000 hours, and only 8.1% performance loss was observed, implying that the durability of HySYS-30 fuel cell system could …


Special Issue In Honor Of Professor Baolian Yi On His 80th Birthday, Chinese Society of Electrochemistry (CSE) 2018 Chinese Chemical Society | Xiamen University

Special Issue In Honor Of Professor Baolian Yi On His 80th Birthday, Chinese Society Of Electrochemistry (Cse)

Journal of Electrochemistry

No abstract provided.


A Review Of Proton Exchange Membrane Fuel Cell Catalyst Layer By Electrospinning, Yong LIU, Han DING, De-chun SI, Jie PENG, Jian-bo ZHANG 2018 College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100081;

A Review Of Proton Exchange Membrane Fuel Cell Catalyst Layer By Electrospinning, Yong Liu, Han Ding, De-Chun Si, Jie Peng, Jian-Bo Zhang

Journal of Electrochemistry

The limitation of catalyst layer for proton exchange membrane fuel cell (PEMFC) in cost, durability and performance constitutes the bottleneck for the commercialization of fuel cell vehicles. Electrospun catalyst layer, with high catalyst utilization, increased triple phase boundary (TPB) and triple phase channel (TPC), has been developed by many researchers. This paper reviews the research progress in the electrospun catalyst layer for PEMFC, combined with the author’s work. Firstly, the development progress of catalyst layer is summarized, and the catalyst layer is classified and analyzed based on its fabrication method and structure character. Next, the fabrication process, physical property characterization, …


Fuel Cell Performance Curve After Mea Optimization Structural Optimization Of Low Pt Membrane Electrode Assembly, Yan RAO, Shang LI, Fen ZHOU, Tian TIAN, Qing ZHONG, Zhao-hui WAN, Jin-ting TAN, Mu PAN 2018 State Key Laboratory of Advanced Technology for Materials Synthesis and Progressing, Hubei Fuel Cell Key Laboratory, Wuhan University of Technology, Wuhan 430070, China;

Fuel Cell Performance Curve After Mea Optimization Structural Optimization Of Low Pt Membrane Electrode Assembly, Yan Rao, Shang Li, Fen Zhou, Tian Tian, Qing Zhong, Zhao-Hui Wan, Jin-Ting Tan, Mu Pan

Journal of Electrochemistry

Membrane electrode assemblies (MEAs) are the key component of proton exchange membrane fuel cell. For a long time, much attention has been paid to develop MEA technology. At present, the research, development and industrialization of fuel cell has entered a new era. More strict requirements for MEA, especially for the reduction of Pt loading with a challenging target of 0.125 mg·W-1 have to be met. In this paper, the performance losses under low Pt loading are analyzed in terms of activation polarization, ohm polarization and mass-transfer polarization. It is proposed that research should be focused on the activity of …


Morphological Control Of Ptcu2 Octahedron And Oxygen Reduction Electrocatalytic Performance Of Ptcu For Fuel Cell, Long-sheng CAO, Lei WAN, Zhi-gang SHAO, Hong-mei YU, Ming HOU, Bao-lian YI 2018 Fuel Cell System and Engineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China;University of Chinese Academy of Sciences, Beijing 100049, China;

Morphological Control Of Ptcu2 Octahedron And Oxygen Reduction Electrocatalytic Performance Of Ptcu For Fuel Cell, Long-Sheng Cao, Lei Wan, Zhi-Gang Shao, Hong-Mei Yu, Ming Hou, Bao-Lian Yi

Journal of Electrochemistry

Platinum acetylacetonate (Pt(acac)2) and copper acetylacetonate (Cu(acac)2) were co-reduced to prepare PtCu2 octahedron alloy catalyst in N,N-dimethylformamiade by solvothermal method. The PtCu2 showed lattice compression, and high ratio of non-oxidized Pt with high electronic binding energy. All those structural features contributed to weak adsorption strength of oxygen species on Pt and lower d-band centre position. The influence of structure-directing agent on morphology of PtCu alloy was systematically studied. In the half cell test, as a result of the uniform morphology and regular octahedron of PtCu2 formed, the mass activity and area specific activity …


Effects Of So2 In Air On Performance Of Direct Methanol Fuel Cell, Bin QIN, Fen-ning JING, Xue-jing SUN, Gong-quan SUN, Hai SUN 2018 Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;University of Chinese Academy of Sciences, Beijing 100039, China;

Effects Of So2 In Air On Performance Of Direct Methanol Fuel Cell, Bin Qin, Fen-Ning Jing, Xue-Jing Sun, Gong-Quan Sun, Hai Sun

Journal of Electrochemistry

Direct methanol fuel cells (DMFC) generally use oxygen as an oxidant. Contaminants such as sulfides and nitrides in the air can affect the performance of the DMFC. In this work, the effects of SO2 on the performance of DMFC were investigated and the mechanism of poisoning was analyzed, by means of constant current discharge curve, polarization performance curve, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In the CV scan, the permeated methanol was oxidized at a low potential to eliminate its effect on the SO2 poisoning behavior test. The results showed that the SO2 poisoning resulted …


Fe-N Doped Hollow Carbon Nanospheres Linked By Carbon Nanotubes For Oxygen Reduction Reaction, Ya-lin ZHANG, Chi CHEN, Liang-liang ZOU, Zhi-qing ZOU, Hui YANG 2018 Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China;University of Chinese Academy of Sciences, Beijing 100049, China;

Fe-N Doped Hollow Carbon Nanospheres Linked By Carbon Nanotubes For Oxygen Reduction Reaction, Ya-Lin Zhang, Chi Chen, Liang-Liang Zou, Zhi-Qing Zou, Hui Yang

Journal of Electrochemistry

The development of non-precious metal catalysts for oxygen reduction reaction (ORR) is essential for large-scale application of proton exchange membrane fuel cells. Herein, we present the in situ formed Fe-N doped hollow carbon nanospheres linked by carbon nanotubes composite, synthesized by using ZIF-8 as sacrificed template to form polydopamine (PDA) hollow nanospheres, followed by complexing with FeCl3, high temperature heat-treatment and NH3-etching. ZIF-8 was gradually decomposed simultaneously with PDA coating due to the loss of Zn2+ grabbed by PDA. NH3 etching resulted in the improved surface area, while the reducibility of NH3 resulted in …


Acid Treated Carbon As Anodic Electrocatalysts Toward Direct Ascorbic Acid Alkaline Membrane Fuel Cells, He-mu CHEN, Chen-xi QIU, Yuan-yuan CONG, Hui-yuan LIU, Zi-hui ZHAI, Yu-jiang SONG 2018 State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China;

Acid Treated Carbon As Anodic Electrocatalysts Toward Direct Ascorbic Acid Alkaline Membrane Fuel Cells, He-Mu Chen, Chen-Xi Qiu, Yuan-Yuan Cong, Hui-Yuan Liu, Zi-Hui Zhai, Yu-Jiang Song

Journal of Electrochemistry

In order to improve the hydrophilicity and electrocatalytic activity, commercial carbon black (BP 2000) was subjected to acid treatment to obtain acid-treated carbon (ATC). The generation of rich oxygen-containing groups on the surface of the ATC was proved by X-ray photoelectron spectra (XPS), Fourier transform-infra red spectra (FTIR), thermogravimetric analysis (TG) and contact angle measurement. UV-vis spectra were firstly recorded to calculate activation energy (Ea) of ascorbic acid (AA) chemical oxidation in alkaline conditions by oxygen in air and the Ea value was determined to be 37.1 kJ·mol-1. Additionally, electrochemical impedance spectra (EIS) were used to evaluate unprecedented …


Pd/C Catalysts For Co2 Electroreduction To Co:Pd Loading Effect, Dun-feng GAO, Cheng-cheng YAN, Guo-xiong WANG, Xin-he BAO 2018 State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China;

Pd/C Catalysts For Co2 Electroreduction To Co:Pd Loading Effect, Dun-Feng Gao, Cheng-Cheng Yan, Guo-Xiong Wang, Xin-He Bao

Journal of Electrochemistry

Nanostructured heterogeneous catalysts have been widely used in the electrochemical carbon dioxide (CO2) reduction reaction (CO2RR), which can simultaneously achieve the electrocatalytic conversion of CO2 to fuels and the storage of renewable energy sources. Carbon supported palladium nanoparticles (Pd/C) catalysts have been previously reported to show excellent CO2RR performance. However, the crucial role of the metal loading in supported electrocatalysts has been rarely reported. In this work, we study the Pd loading effect on the structure of Pd/C catalysts as well as their activity and selectivity of CO2RR to CO. The …


Recent Progress In Pt-Based Catalysts For Oxygen Reduction Reaction, Jing LI, Xin FENG, Zi-dong WEI 2018 School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China;

Recent Progress In Pt-Based Catalysts For Oxygen Reduction Reaction, Jing Li, Xin Feng, Zi-Dong Wei

Journal of Electrochemistry

One major challenge for a large-scale commercialization of the proton-exchange membrane fuel cells (PEMFCs) technologies that enable a shift to ‘zero-emission’ personal transportation, is the expensive and unstable Pt catalysts, which are mainly used to catalyze the sluggish kinetics of the oxygen reduction reaction (ORR) occurred on the air electrode of PEMFCs. Many research works have targets to improve the stability of Pt-based catalysts and to construct Pt/transitional metal alloys with low Pt loading amount. Herein, we provide a minireview for the Pt-based ORR catalysts based on our recent work, which covers a brief background introduction, the stability improvement of …


Facile Synthesis Of Pt-Cu Alloy Nanodendrites As High-Performance Electrocatalysts For Oxygen Reduction Reaction, Liu-xuan LUO, Guang-hua WEI, Shui-yun SHEN, Feng-juan ZHU, Chang-chun KE, Xiao-hui YAN, Jun-liang ZHANG 2018 Institute of Fuel Cells, School of Mechanical Engineering, MOE Key Laboratory of Power & Machinery Engineering;

Facile Synthesis Of Pt-Cu Alloy Nanodendrites As High-Performance Electrocatalysts For Oxygen Reduction Reaction, Liu-Xuan Luo, Guang-Hua Wei, Shui-Yun Shen, Feng-Juan Zhu, Chang-Chun Ke, Xiao-Hui Yan, Jun-Liang Zhang

Journal of Electrochemistry

Structures and compositions have significant effects on the catalytic properties of nanomaterials. Herein, a facile etching-based method was employed to synthesize Pt-Cu nanodendrites (NDs) with uniform and homogeneous alloy structures for enhancing oxygen reduction reaction (ORR). The formation of dendritic morphology was ascribed to the etching effect caused by the oxidative etchants of the Br-/O2 pair. The atomic ratio of Pt/Cu in Pt-Cu NDs could be easily tuned by altering the ratio of the Pt/Cu precursors, without deteriorating the dendritic morphology. The most active carbon-supported Pt1Cu1 NDs (Pt1Cu1 NDs/C) exhibited the …


Atom-Specific Activation In Co Oxidation, Simon Schreck, Elias Diesen, Jerry LaRue, Hirohito Ogasawara, Kess Marks, Dennis Nordlund, Matthew Weston, Martin Beye, Filippo Cavalca, Fivos Perakis, Jonas Sellberg, André Eilert, Kyung Hwan Kim, Giacomo Coslovich, Ryan Coffee, Jacek Krzywinski, Alex Reid, Stefan Moeller, Alberto Lutman, Henrik Öström, Lars G. M. Pettersson, Anders Nilsson 2018 Stockholm University

Atom-Specific Activation In Co Oxidation, Simon Schreck, Elias Diesen, Jerry Larue, Hirohito Ogasawara, Kess Marks, Dennis Nordlund, Matthew Weston, Martin Beye, Filippo Cavalca, Fivos Perakis, Jonas Sellberg, André Eilert, Kyung Hwan Kim, Giacomo Coslovich, Ryan Coffee, Jacek Krzywinski, Alex Reid, Stefan Moeller, Alberto Lutman, Henrik Öström, Lars G. M. Pettersson, Anders Nilsson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We report on atom-specific activation of CO oxidation on Ru(0001) via resonant X-ray excitation. We show that resonant 1s core-level excitation of atomically adsorbed oxygen in the co-adsorbed phase of CO and oxygen directly drives CO oxidation. We separate this direct resonant channel from indirectly driven oxidation via X-ray induced substrate heating. Based on density functional theory calculations, we identify the valence-excited state created by the Auger decay as the driving electronic state for direct CO oxidation. We utilized the fresh-slice multi-pulse mode at the Linac Coherent Light Source that provided time-overlapped and 30 fs delayed pairs of soft …


Development And Thermodynamic Analysis Of An Integrated Mild/Partial Gasification Combined Cycle (Impgc) Under Green And Brown Field Conditions With And Without Carbon Capture, Henry A. Long III 2018 University of New Orleans

Development And Thermodynamic Analysis Of An Integrated Mild/Partial Gasification Combined Cycle (Impgc) Under Green And Brown Field Conditions With And Without Carbon Capture, Henry A. Long Iii

LSU New Orleans Theses and Dissertations

Coal is a very prominent energy source in the world, but it is environmentally unattractive due to its high sulfur and ash content as well as its alleged contribution towards climate change, but it is affordable, abundant, and has high energy content. Thus, utilizing coal in a cleaner and more efficient way has become necessary. One promising clean coal technology involves fully gasifying coal into synthesis gas, cleaning it, and feeding it into a high-efficiency combined cycle, such as an Integrated Gasification Combined Cycle (IGCC). Inspired by the recent success of warn gas cleanup (WGCU), mild and partial gasification are …


Optimization Of Useful Hard X-Ray Photochemistry, David Lewis Goldberger 2018 University of Nevada, Las Vegas

Optimization Of Useful Hard X-Ray Photochemistry, David Lewis Goldberger

UNLV Theses, Dissertations, Professional Papers, and Capstones

X-ray induced damage is generally considered a nuisance, but in the field of Useful Hard X-ray Photochemistry we harness the highly ionizing and penetrating properties of hard X-rays (> 7 keV) to initiate novel photochemical decomposition and synthesis at ambient and extreme conditions. Preliminary experiments suggest that the energy of irradiating photons and the sample pressure play roles in determining the nature of X-ray induced damage. Here, we present the X-ray energy dependence of damage induced in strontium oxalate, strontium nitrate, and barium nitrate, as well as the pressure dependence of X-ray induced damage of strontium oxalate. Our results indicate …


The Investigation Of The Chlorine Initiated Oxidation Of 2-Phenylethanol And Stability Of Superalkali Lithium Substituted Silyls., Adam Otten 2018 The University of San Francisco

The Investigation Of The Chlorine Initiated Oxidation Of 2-Phenylethanol And Stability Of Superalkali Lithium Substituted Silyls., Adam Otten

Master's Theses

This thesis investigates the combustion potential of 2-phenylethanol and the superalkali properties of small lithium substituted silicon compounds. All combustion experiments were performed at the Advanced Light Source of Lawrence Berkeley National Laboratory at the Chemical Dynamics Beamline 9.0.2. The chlorine initiated oxidation of 2PE was investigated at 298 and 550 K using a multiplex photoionization mass spectrometer, coupled with the tunable vacuum ultraviolet radiation. Reaction products were identified using kinetic time traces and photoionization spectra.

Additionally, the stability of small superalkali silicon-lithium compounds has also been investigated. All structures and energetics were calculated using the CBS-QB3 composite method.

The …


Heat And Work, The First Law Of Thermodynamics From The Boltzmann Pov, Carl W. David 2018 University of Connecticut

Heat And Work, The First Law Of Thermodynamics From The Boltzmann Pov, Carl W. David

Chemistry Education Materials

The First Law of Thermodynamics is discussed in terms of the Boltzmann distribution.


Effect Of Network Structure On Free Volume And Gas Transport Properties Of Thiol-Ene And Epoxy-Amine Networks, Ramesh Krishnan Ramakrishnan 2018 University of Southern Mississippi

Effect Of Network Structure On Free Volume And Gas Transport Properties Of Thiol-Ene And Epoxy-Amine Networks, Ramesh Krishnan Ramakrishnan

Dissertations

Network parameters such as cross-link density or intermolecular interactions were used as effective parameters to control polymer chain packing or free volume and thereby control the mass transport properties of networks.

A series of polyethylene glycol (PEG) based thiol-ene elastomeric networks having a broad range of molecular weight between cross-links, Mc, (inverse of cross-link density) was prepared. The specific volume of the networks was studied as a function of temperature and pressure using high pressure dilatometry, and the obtained PVT data was fit using Simha-Somcynsky equation of state (S-S eos) analysis. Fractional free volume, quantified through S-S eos …


Molecular Dynamics Investigation Of The Thermodynamics Of Nanoscale Droplets And Kinetics Of Weakly Correlated Systems, Kai Yang Leong 2018 University of Arkansas, Fayetteville

Molecular Dynamics Investigation Of The Thermodynamics Of Nanoscale Droplets And Kinetics Of Weakly Correlated Systems, Kai Yang Leong

Graduate Theses and Dissertations

The surface tension of nanoscale droplets of water was studied with molecular dynamics simulations using the BLYPSP-4F water potential. The internal pressure of the droplet was measured using a correlation between the pressure and density, established through a series of bulk simulations performed at pressures from 1 to 1000 bar. Such a procedure allows for reliable determination of internal pressure without the need to calculate the local Virial. The surface tension, estimated with the Young-Laplace relation, shows a good agreement with the Tolman equation with a Tolman length of -0.48 Å. The interface of a liquid water droplet is shown …


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