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Efficient and stable PtFe alloy catalyst for electrocatalytic methanol oxidation with high resistance to CO
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作者 Qian Yang Sifan Zhang +5 位作者 Fengshun Wu Lihua Zhu Guang Li Mingzhi Chen An Pei Yingliang Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期327-336,I0008,共11页
Direct methanol fuel cells(DMFC) are widely considered to be an ideal green energy conversion device but their widespread applications are limited by the high price of the Pt-based catalysts and the instability in ter... Direct methanol fuel cells(DMFC) are widely considered to be an ideal green energy conversion device but their widespread applications are limited by the high price of the Pt-based catalysts and the instability in terms of surface CO toxicity in long-term operation.Herein,the PtFe alloy nanoparticles(NPs) with small particle size(~4.12 nm) supported on carbon black catalysts with different Pt/Fe atomic ratios(Pt_(1)Fe_(2)/C,Pt_(3)Fe_(4)/C,Pt_(1)Fe_(1)/C,and Pt_(2)Fe_(1)/C) are successfully prepared for enhanced anti-CO poisoning during methanol oxidation reaction(MOR).The optimal atomic ratio of Pt/Fe for the MOR is 1:2,and the mass activity of Pt_(1)Fe_(2)/C(5.40 A mg_(Pt)^(-1)) is 13.5 times higher than that of conventional commercial Pt/C(Pt/C-JM)(0.40 A mg_(Pt)^(-1)).The introduction of Fe into the Pt lattice forms the PtFe alloy phase,and the electron density of Pt is reduced after forming the PtFe alloy.In-situ Fourier transform infrared results indicate that the addition of oxyphilic metal Fe has reduced the adsorption of reactant molecules on Pt during the MOR.The doping of Fe atoms helps to desorb toxic intermediates and regenerate Pt active sites,promoting the cleavage of C-O bonds with good selectivity of CO_(2)(58.1%).Moreover,the Pt_(1)Fe_(2)/C catalyst exhibits higher CO tolerance,methanol electrooxidation activity,and long-term stability than other Pt_(x)Fe_(y)/C catalysts. 展开更多
关键词 Alloy catalyst PTFE methanol oxidation In-situ FTIR CO resistance
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Precision tuning of highly efficient Pt-based ternary alloys on nitrogen-doped multi-wall carbon nanotubes for methanol oxidation reaction
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作者 Xingqun Zheng Zhengcheng Wang +3 位作者 Qian Zhou Qingmei Wang Wei He Shun Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期242-251,I0006,共11页
The electrochemical methanol oxidation is a crucial reaction in the conversion of renewable energy.To enable the widespread adoption of direct methanol fuel cells(DMFCs),it is essential to create and engineer catalyst... The electrochemical methanol oxidation is a crucial reaction in the conversion of renewable energy.To enable the widespread adoption of direct methanol fuel cells(DMFCs),it is essential to create and engineer catalysts that are both highly effective and robust for conducting the methanol oxidation reaction(MOR).In this work,trimetallic PtCoRu electrocatalysts on nitrogen-doped carbon and multi-wall carbon nanotubes(PtCoRu@NC/MWCNTs)were prepared through a two-pot synthetic strategy.The acceleration of CO oxidation to CO_(2) and the blocking of CO reduction on adjacent Pt active sites were attributed to the crucial role played by cobalt atoms in the as-prepared electrocatalysts.The precise control of Co atoms loading was achieved through precursor stoichiometry.Various physicochemical techniques were employed to analyze the morphology,element composition,and electronic state of the catalyst.Electrochemical investigations and theoretical calculations confirmed that the Pt_(1)Co_(3)Ru_(1)@NC/MWCNTs exhibit excellent electrocatalytic performance and durability for the process of MOR.The enhanced MOR activity can be attributed to the synergistic effect between the multiple elements resulting from precisely controlled Co loading content on surface of the electrocatalyst,which facilitates efficient charge transfer.This interaction between the multiple components also modifies the electronic structures of active sites,thereby promoting the conversion of intermediates and accelerating the MOR process.Thus,achieving precise control over Co loading in PtCoRu@NC/MWCNTs would enable the development of high-performance catalysts for DMFCs. 展开更多
关键词 Ternary alloys ELECTROCATALYSTS methanol oxidation reaction Electron transfer Theoretical calculations
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Tungsten carbide-reduced graphene oxide intercalation compound as co-catalyst for methanol oxidation 被引量:3
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作者 施梅勤 章文天 +2 位作者 李影影 褚有群 马淳安 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期1851-1859,共9页
Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The met... Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The metatungstate ion,[H2W(12)O(40)]^6-,is assembled on thiourea-modified graphene oxide(GO) by an impregnation method.The WC NPs,with a mean diameter of 1.5 nm,are obtained through a process whereby ammonium metatungstate first turns to WS2,which then forms an intercalation compound with RGO before growing,in situ,to WC NPs.The Pt/WC-RGO electrocatalysts are fabricated by a microwave-assisted method.The intimate contacts between Pt,WC,and RGO are confirmed by X-ray diffraction,scanning electron microscope,transmission electron microscope,and Raman spectroscopy.For methanol oxidation,the Pt/WC-RGO electrocatalyst exhibited an electrochemical surface area value of 246.1 m^2/g Pt and a peak current density of1364.7 mA/mg Pt,which are,respectively,3.66 and 4.77 times greater than those of commercial Pt/C electrocatalyst(67.2 m^2/g Pt,286.0 mA/mg Pt).The excellent CO-poisoning resistance and long-term stability of the electrocatalyst are also evidenced by CO stripping,chronoamperometry,and accelerated durability testing.Because Pt/WC-RGO has higher catalytic activity compared with that of commercial Pt/C,as a result of its intercalated structure and synergistic effect,less Pt will be required for the same performance,which in turn will reduce the cost of the fuel cell.The present method is facile,efficient,and scalable for mass production of the nanomaterials. 展开更多
关键词 Tungsten carbide-reduced graphene oxide Intercalation compound THIOUREA ANCHORING methanol oxidation
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Study on Methanol Oxidation at Pt and PtRu Electrodes by Combining in situ Infrared Spectroscopy and Differential Electrochemical Mass Spectrometry 被引量:1
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作者 陶骞 陈微 +2 位作者 姚瑶 Ammar Bin Yousaf 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第5期541-547,I0003,共8页
Methanol oxidation reaction (MOR) at Pt and Pt electrode surface deposited with various amounts of Ru (denoted as PtxRuy, nominal coverage y is 0.17, 0.27, and 0.44 ML) in 0.1 mol/L HClO4+0.5 mol/L MeOH has been ... Methanol oxidation reaction (MOR) at Pt and Pt electrode surface deposited with various amounts of Ru (denoted as PtxRuy, nominal coverage y is 0.17, 0.27, and 0.44 ML) in 0.1 mol/L HClO4+0.5 mol/L MeOH has been studied under potentiostatic conditions by in situ FTIR spectroscopy in attenuated-total-reflection con guration and di erential electro-chemical mass spectrometry under controlled flow conditions. Results reveal that (i) CO is the only methanol-related adsorbate observed by IR spectroscopy at all the Pt and PtRu electrodes examined at potentials from 0.3 V to 0.6 V (vs. RHE); (ii) at Pt0.56Ru0.44, two IR bands, one from CO adsorbed at Ru islands and the other from COL at Pt substrate are detected, while at other electrodes, only a single band for COL adsorbed at Pt is observed; (iii) MOR activity decreases in the order of Pt0.73Ru0.27〉Pt0.56Ru0.44〉Pt0.83Ru0.17〉Pt; (iv) at 0.5 V, MOR at Pt0.73Ru0.27 reaches a current e ciency of 50% for CO2 production, the turn-over frequency from CH3OH to CO2 is ca. 0.1 molecule/(site sec). Suggestions for further improving of PtRu catalysts for MOR are provided. 展开更多
关键词 Differential electrochemical mass spectrometry Electrochemical in situ infrared spectroscopy methanol oxidation PtRu electrode Current efficiency
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Controllable synthesis of grain boundary-enriched Pt nanoworms decorated on graphitic carbon nanosheets for ultrahigh methanol oxidation catalytic activity 被引量:9
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作者 Huajie Huang Yujie Wei +5 位作者 Ying Yang Minmin Yan Haiyan He Quanguo Jiang Xiaofei Yang Jixin Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第6期601-609,I0014,共10页
Although one-dimensional Pt nanocrystals have long been regarded as ideal electrode catalysts for fuel cells,the synthetic techniques commonly involve the use of various complicated templates or surfactants,which have... Although one-dimensional Pt nanocrystals have long been regarded as ideal electrode catalysts for fuel cells,the synthetic techniques commonly involve the use of various complicated templates or surfactants,which have largely hampered their large-scale industrial application.Herein,we present a convenient and cost-effective approach to the stereoassembly of quasi-one-dimensional grain boundary-enriched Pt nanoworms on nitrogen-doped low-defect graphitic carbon nanosheets(Pt NWs/NL-CNS).Benefiting from its numerous catalytically active grain boundaries as well as optimized electronic structure,the as-derived Pt NWs/NL-CNS catalyst possesses exceptionally good electrocatalytic properties for methanol oxidation,including an ultrahigh mass activity of 1949.5 mA mg^(-1), reliable long-term durability,and strong poison tolerance,affording one of the most active Pt-based electrocatalysts for methanol oxidation reaction.Density functional theory calculation further reveals that the formation of worm-shape Pt morphology is attributed to the modified electronic structure as well as controllable defect density of the carbon matrix,which could also weaken the adsorption ability of Pt towards CO molecule and meanwhile synergistically promotes the catalytic reaction kinetics. 展开更多
关键词 Platinum nanoworm Nitrogen doping Low defect Carbon nanosheet methanol oxidation
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Research advances in unsupported Pt-based catalysts for electrochemical methanol oxidation 被引量:8
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作者 Xin Long Tian Lijuan Wang +2 位作者 Peilin Deng Yu Chen Bao Yu Xia 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1067-1076,共10页
Direct methanol fuel cells are one of the most promising alternative energy technologies in the foreseeable future, but its successful commercialization in large scale is still heavily hindered by several technical sh... Direct methanol fuel cells are one of the most promising alternative energy technologies in the foreseeable future, but its successful commercialization in large scale is still heavily hindered by several technical shortfalls, especially the undesirable activity and durability issues of electrocatalysts toward methanol oxidation reaction. In light of these challenges, the inherent advantages of unsupported Pt based nanostructures demonstrate their great potentials as durable and efficient electrocatalysts for direct methanol fuel cells. This review will summarize recent achievements of unsupported Pt-based electrocatalysts toward methanol oxidation, with highlighting the interactions between the performance and structure tailoring and composition modulating. At last, a perspective is proposed for the upcoming challenges and possible opportunities to further prompt the practical application of unsupported Pt-based electrocatalysts for direct methanol fuel cells. 展开更多
关键词 Unsupported Pt nanostructures ALLOYS Core/Shell methanol oxidation
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Hierarchically skeletal multi-layered Pt-Ni nanocrystals for highly efficient oxygen reduction and methanol oxidation reactions 被引量:6
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作者 Shibo Li Zhi Qun Tian +5 位作者 Yang Liu Zheng Jang Syed Waqar Hasan Xingfa Chen Panagiotis Tsiakaras Pei Kang Shen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第4期648-657,共10页
Pt based materials are the most efficient electrocatalysts for the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR)in fuel cells.Maximizing the utilization of Pt based materials by modulating their m... Pt based materials are the most efficient electrocatalysts for the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR)in fuel cells.Maximizing the utilization of Pt based materials by modulating their morphologies to expose more active sites is a fundamental objective for the practical application of fuel cells.Herein,we report a new class of hierarchically skeletal Pt-Ni nanocrystals(HSNs)with a multi-layered structure,prepared by an inorganic acid-induced solvothermal method.The addition of H_(2)SO_(4)to the synthetic protocol provides a critical trigger for the successful growth of Pt-Ni nanocrystals with the desired structure.The Pt-Ni HSNs synthesized by this method exhibit enhanced mass activity of 1.25 A mgpt−1 at 0.9 V(versus the reversible hydrogen electrode)towards ORR in 0.1-M HClO_(4),which is superior to that of Pt-Ni multi-branched nanocrystals obtained by the same method in the absence of inorganic acid;it is additionally 8.9-fold higher than that of the commercial Pt/C catalyst.Meanwhile,it displays enhanced stability,with only 21.6%mass activity loss after 10,000 cycles(0.6–1.0 V)for ORR.Furthermore,the Pt-Ni HSNs show enhanced activity and anti-toxic ability in CO for MOR.The superb activity of the Pt-Ni HSNs for ORR and MOR is fully attributed to an extensively exposed electrochemical surface area and high intrinsic activity,induced by strain effects,provided by the unique hierarchically skeletal alloy structure.The novel open and hierarchical structure of Pt-Ni alloy provides a promising approach for significant improvements of the activity of Pt based alloy electrocatalysts. 展开更多
关键词 Hierarchically skeletal Pt-Ni NANOCRYSTALS SELF-ASSEMBLY Solvent thermal method Oxygen reduction reaction methanol oxidation reaction Fuel cells ACTIVITY
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Effects of CeO_(2)pre-calcined at different temperatures on the performance of Pt/CeO_(2)-C electrocatalyst for methanol oxidation reaction 被引量:8
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作者 Guo-qing Li Pu-kang Wen +6 位作者 Chen-qiang Gao Tian-yi Zhang Jun-yang Hu Yu-hao Zhang Shi-you Guan Qing-feng Li Bing Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第7期1224-1232,共9页
Pt/CeO_(2)-C catalysts with CeO_(2)pre-calcined at 300-600 ℃were synthesized by combining hydrothermal calcination and wet im-pregnation.The effects of the pre-calcined CeO_(2)on the performance of Pt/CeO_(2)-C catal... Pt/CeO_(2)-C catalysts with CeO_(2)pre-calcined at 300-600 ℃were synthesized by combining hydrothermal calcination and wet im-pregnation.The effects of the pre-calcined CeO_(2)on the performance of Pt/CeO_(2)-C catalysts in methanol oxidation were investigated.The Pt/CeO_(2)-C catalysts with pre-calcined CeO_(2)at 300-600 ℃showed an average particle size of 2.6-2.9 nm and exhibited better methanol elec-tro-oxidation catalytic activity than the commercial Pt/C catalyst.In specific,the Pt/CeO_(2)-C catalysts with pre-calcined CeO_(2)at 400 ℃dis-played the highest electrochemical surface area value of 68.14 m2·g−1 and If/Ib ratio(the ratio of the forward scanning peak current density(If)and the backward scanning peak current density(Ib))of 1.26,which are considerably larger than those(53.23 m2·g−1 and 0.79,respectively)of the commercial Pt/C catalyst,implying greatly enhanced CO tolerance. 展开更多
关键词 direct methanol fuel cell platinum/cerium dioxide-carbon ELECTROCATALYST methanol oxidation
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Rational design ternary platinum based electrocatalysts for effective methanol oxidation reaction 被引量:6
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作者 Hao Tian Daoxiong Wu +9 位作者 Jing Li Junming Luo Chunman Jia Zhongxin Liu Wei Huang Qi Chen Chong Michael Shim Peilin Deng Yijun Shen Xinlong Tian 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期230-235,I0007,共7页
Exploring effective, durable, and affordable electrocatalysts of methanol oxidation reaction(MOR) is of vital significance for the industrial application of direct methanol fuel cells. Herein, an efficient, general,an... Exploring effective, durable, and affordable electrocatalysts of methanol oxidation reaction(MOR) is of vital significance for the industrial application of direct methanol fuel cells. Herein, an efficient, general,and expandable method is developed to synthesis two-dimensional(2D) ternary Pt Bi M nanoplates(NPLs), in which various M(Co, Ni, Cu, Zn, Sn) is severed as the third component to the binary Pt Bi system. The MOR performance of Pt Bi M NPLs is entirely investigated, demonstrating that both the MOR activity and durability is enhanced with the introduction of the additional composition. Pt3Bi3Zn NPLs shows much higher MOR activity and stability than that of the Pt Bi counterparts, not to mention the current advanced Pt Ru/C and Pt/C catalysts. The prominent performances are attributed to the modulated electronic structure of the surface Pt in Pt Bi NPLs by the addition of Zn, resulting in a weakened affination between Pt and the adsorbed poisoning species(mainly CO) compared with Pt Bi NPLs, verified by density functional theory(DFT) calculations. In addition, the absorbed OH can be generated on the surface of Zn atom due to its favorable water activation properties, thus the CO removal on the adjacent Pt atoms is accelerated, further leading to a high activity and anti-poisoning performance of the resulting Pt_(3)Bi_(3)Zn catalyst. This work provides new insights and robust strategy for highly efficient MOR electrocatalyst with extraordinary anti-poisoning performance and stability. 展开更多
关键词 Fuel cells Ternary nanoplates DURABILITY methanol oxidation reaction Anti-poisoning
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Ultrafine Pt nanoparticles supported on double-shelled C/TiO2 hollow spheres material as highly efficient methanol oxidation catalysts 被引量:5
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作者 Xiaoyu Yue Yuguang Pu +2 位作者 Wen Zhang Ting Zhang Wei Gao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第10期275-282,共8页
Catalyst support is extremely important for future fuel cell devices.In this work,we developed doubleshelled C/TiO2(DSCT)hollow spheres as an excellent catalyst support via a template-directed method.The combination o... Catalyst support is extremely important for future fuel cell devices.In this work,we developed doubleshelled C/TiO2(DSCT)hollow spheres as an excellent catalyst support via a template-directed method.The combination of hollow structure,TiO2 shell and carbon layer results in excellent electron conductivity,electrocatalytic activity,and chemical stability.These uniformed DSCT hollow spheres are used as catalyst support to synthesize Pt/DSCT hollow spheres electrocatalyst.The resulting Pt/DSCT hollow spheres exhibited high catalytic performance with a current density of 462 mA mg^-1 for methanol oxidation reaction,which is 2.52 times higher than that of the commercial Pt/C.Furthermore,the increased tolerance to carbonaceous poisoning with a higher If/Ibratio and a better long-term stability in acid media suggests that the DSCT hollow sphere is a promising C/TiO2-based catalyst support for direct methanol fuel cells applications. 展开更多
关键词 Catalyst support C/TiO2 hollow sphere Metal-support interactions methanol oxidation reaction
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Composition-controlled synthesis of platinum and palladium nanoalloys as highly active electrocatalysts for methanol oxidation 被引量:4
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作者 Haiqiang Zhao Weihong Qi +2 位作者 Xinfeng Zhou Haofei Wu Yejun Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期342-349,共8页
Platinum and palladium(PtPd)alloy nanoparticles(NPs)are excellent catalysts for direct methanol fuel cells.In this study,we developed PtPd alloy NPs through the co‐reduction of K2PtCl4and Na2PdCl4in a polyol synthesi... Platinum and palladium(PtPd)alloy nanoparticles(NPs)are excellent catalysts for direct methanol fuel cells.In this study,we developed PtPd alloy NPs through the co‐reduction of K2PtCl4and Na2PdCl4in a polyol synthesis environment.During the reaction,the feed molar ratio of the two precursors was carried over to the final products,which have a narrow size distribution with a mean size of approximately4nm.The catalytic activity for methanol oxidation reactions possible depends closely on the composition of as‐prepared PtPd alloy NPs,and the NPs with a Pt atomic percentage of approximately75%result in higher activity and stability with a mass specific activity that is7times greater than that of commercial Pt/C catalysts.The results indicate that through composition control,PtPd alloy NPs can improve the effectiveness of catalytic performance. 展开更多
关键词 Platinum and palladium alloy nanoparticles Composition and size control methanol oxidation
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Facile synthesis of 3D nanoporous Pd/Co_2O_3 composites with enhanced catalytic performance for methanol oxidation 被引量:3
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作者 Yan-yan SONG Dong DUAN +2 位作者 Wen-yu SHI Hai-yang WANG Zhan-bo SUN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第4期676-686,共11页
To simultaneously reduce noble metal Pd usage and enhance electrocatalytic performance for methanol oxidation,Pd/Co2O3 composites with ultrafine three-dimensional(3D)nanoporous structures were designed and synthesized... To simultaneously reduce noble metal Pd usage and enhance electrocatalytic performance for methanol oxidation,Pd/Co2O3 composites with ultrafine three-dimensional(3D)nanoporous structures were designed and synthesized by simple one-step dealloying of a melt-spun Al-Pd-Co alloy with an alkaline solution.Their electrocatalytic activity in alkaline media was determined by a Versa-STAT MC workstation.The results indicate that the typical sizes of the ligaments and pores of the composites were approximately 8-9 nm.The Co2O3 was uniformly distributed on the Pd ligament surface.Among the as-prepared samples,the nanoporous Pd/Co2O3 composite generated from dealloying of the Al84.5Pd15Co0.5 alloy had the best electrocatalytic activity,and its activity was enhanced by approximately 230%compared with the nanoporous Pd from dealloying of Al85Pd15.The improvement of the electrocatalytic performance was mainly attributed to the electronic modification effect between Pd and Co as well as the bifunctional mechanism between Pd and Co2O3. 展开更多
关键词 nanoporous Pd/Co2O3 DEALLOYING Al-Pd-Co alloy electrocatalytic performance methanol oxidation
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Surface elemental distribution effect of Pt-Pb hexagonal nanoplates for electrocatalytic methanol oxidation reaction 被引量:2
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作者 Hee Jin Kim Yong-Deok Ahn +4 位作者 Jeonghyeon Kim Kyoung-Su Kim Yeon Uk Jeong Jong Wook Hong Sang-Il Choi 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第5期813-819,共7页
Bimetallic Pt-based catalysts have been extensively investigated to enhance the performance of direct methanol fuel cells(DMFCs) because CO, a by-product, reduces the activity of the pure Pt catalysts. Herein, we synt... Bimetallic Pt-based catalysts have been extensively investigated to enhance the performance of direct methanol fuel cells(DMFCs) because CO, a by-product, reduces the activity of the pure Pt catalysts. Herein, we synthesized Pt-Pb hexagonal nanoplates as a model catalyst for the methanol oxidation reaction(MOR) and further controlled the Pt and Pb distributions on the surface of the nanoplates through acetic acid(HAc) treatment. As a result, we obtained Pt-Pb nanoplates and HAc-treated Pt-Pb nanoplates with homogeneous and heterogeneous distributions of the Pt-Pb alloy surfaces, respectively. We showed that the MOR activity and stability of the Pt-Pb nanoplates improved compared to those of the HAc-treated Pt-Pb nanoplates, mainly due to the enhanced CO tolerance and the modified electronic structure of Pt under the influence of the oxophilic Pb. 展开更多
关键词 Platinum Lead NANOPLATE Surface atomic distribution methanol oxidation reaction
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Pore structure effects on the kinetics of methanol oxidation over nanocast mesoporous perovskites 被引量:2
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作者 Mahesh M.Nair Freddy Kleitz Serge Kaliaguine 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第1期32-42,共11页
Mesoporous LaMnO3 perovskite catalysts with high surface area were synthesized by using the recently developed hard templating method designated as "nanocasting".Ordered mesoporous silica designated as SBA-15 was us... Mesoporous LaMnO3 perovskite catalysts with high surface area were synthesized by using the recently developed hard templating method designated as "nanocasting".Ordered mesoporous silica designated as SBA-15 was used as the hard template.It was found that the surface area of the nanocast perovskites can be tuned(80–190 m2/g)by varying the aging temperature of the SBA-15 template.Nanocast LaMnO3 catalysts showed high conversion efficiencies for the total oxidation of methanol under steady state conditions,the one with the highest value of surface area being the best catalysts,as expected.Kinetic studies were performed for all of the synthesized catalysts.Rate constants were found to vary in accordance with the specific surface area of the nanocast catalyst which depends on the aging temperature of the parent template.From the rate constants obtained from experimental conversions at various space velocities(19500 to 78200 h〈sup〉–1),values of activation energy and pre-exponential factor for the three nanocast LaMnO3 catalysts were determined by the linear regression of the Arrhenius plot.It is observed that the activation energy for all the catalysts remain constant irrespective of the variation in specific surface area.Further,a linear relationship was found to exist between the pre-exponential factor and specific surface areas of the catalysts indicating that the rates per unit surface area remains the same for all the catalysts. 展开更多
关键词 Mesoporous perovskites High surface area NANOCASTING methanol oxidation KINETICS
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Platinum nanoparticles coated by graphene layers: A low-metal loading catalyst for methanol oxidation in alkaline media 被引量:2
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作者 Camelia Berghian-Grosan Teodora Radu +5 位作者 Alexandru R.Biris Monica Dan Cezara Voice Fumiya Watanabe Alexandru S.Biris Adriana Vulcu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第1期81-88,I0004,共9页
Platinum catalysts play a major role in the large scale commercialization of direct methanol fuel cells(DMFC).Here,we present a procedure to create a nanostructural graphene-platinum(Gr Pt)composite containing a small... Platinum catalysts play a major role in the large scale commercialization of direct methanol fuel cells(DMFC).Here,we present a procedure to create a nanostructural graphene-platinum(Gr Pt)composite containing a small amount(5.3 wt%)of platinum nanoparticles coated with at least four layers of graphene.The composite,as Gr Pt ink,was deposited on a glassy carbon electrode and its electrocatalytic activity in a methanol oxidation reaction(MOR)was evaluated in a 1 M CH3OH/1 M NaOH solution.The results indicated an enhanced catalytic performance of GrPt towards MOR in alkaline media compared with the Pt/C material.Electron energy-loss spectroscopy and X-ray photoelectron spectroscopy(recorded before and after the electrochemical assays)were employed to analyze the changes in the chemical composition of the nanomaterial and to explain the transformations that took place at the electrode surface.Our findings suggest that growing of graphene on platinum nanoparticles improve the catalytic performance of platinum-graphene composites towards MOR in alkaline media. 展开更多
关键词 Low-platinum loading electrocatalyst Graphene layers methanol oxidation ELECTROCATALYSIS Alkaline fuel cell
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Bimetallic Pt–Ru covalently bonded on carbon nanotubes for efficient methanol oxidation 被引量:2
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作者 Ting Zhang Wanzong Wang +3 位作者 Zheng Ma Lei Bai Yue Yao Dongqing Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第9期1816-1823,共8页
Platinum-based nanocomposites have been considered as one of the most promising catalysts for methanol oxidation reactions(MORs), which yet still suffer from low electrochemical activity and electron-transfer properti... Platinum-based nanocomposites have been considered as one of the most promising catalysts for methanol oxidation reactions(MORs), which yet still suffer from low electrochemical activity and electron-transfer properties. Apart from van-der-Waals heterostructures,herein, we report a novel nanocomposite with the structure of Pt–Ru bimetallic nanoparticles covalently-bonded onto multi-walled carbon nanotubes (MWCNTs)(Pt–Ru@MWCNT), which have been successfully fabricated via a facile and green synthesis method. It is demonstrated that the Pt–Ru@MWCNT nanocomposite possesses much enhanced electrocatalytic activity with the electrochemical active surface area(ECSA) of 110.4 m^(2)·g^(-1)for Pt towards MOR, which is 2.67 and 4.0 times higher than those of 20wt%commercial Pt@C and Pt-based nanocomposite prepared by other method, due to the improved electron-transfer properties originated from M–O–C covalent bonds. This work provides us a new strategy for the structural design of highly-efficient electrocatalysts in boosting MOR performance. 展开更多
关键词 bimetallic Pt-Ru nanocomposite high loaded functionalized multi-walled carbon nanotubes methanol oxidation green hydrothermal synthesis
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Robust copper nanocrystal/nitrogen-doped carbon monoliths as carbon monoxide-resistant electrodes for methanol oxidation reaction 被引量:1
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作者 Fei Chen Na Wu +4 位作者 Meixu Zhai Xue Zhang Ruihong Guo Tuoping Hu Mingming Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期247-255,共9页
Noble metal-based electrocatalysts present high activities for methanol oxidation reaction(MOR),but are limited by their high cost,low stability and poor resistance to carbon monoxide(CO) poisoning.The development of ... Noble metal-based electrocatalysts present high activities for methanol oxidation reaction(MOR),but are limited by their high cost,low stability and poor resistance to carbon monoxide(CO) poisoning.The development of active and stable non-noble metal electrocatalysts for MOR is desired,but remains a challenge.Herein,we report a simple strategy to make copper nanocrystal/nitrogen-doped carbon(Cu/N-C)monoliths,which can serve as active and robust electrodes for MOR.Copper nanocrystals were electrochemically deposited onto a conductive polyaniline hydrogel and calcined to form Cu/N-C monolith,where the active copper nanocrystals are protected by nitrogen-doped carbon.Owing to their extremely high electrical conductivity(1.25 × 10^(5) S cm^(-1)) and mechanical robustness,these Cu/N-C monoliths can be directly used as electrodes for MOR,without using substrates or additives.The optimal Cu/N-C(FT)@500 monolith shows a high MOR activity of 189 mA cm^(-2) at 0.6 V vs.SCE in alkaline methanol solution,superior to most of reported Cu-based MOR catalysts.Cu/N-C(FT)@500 also presents a better stability than Pt/C catalyst in the long-term MOR test at high current densities.Upon carbon monoxide(CO) poisoning,Cu/N-C(FT)@500 retains 96% of its MOR activity,far exceeding the performance of Pt/C catalyst(61% retention).Owing to its facile synthesis,outstanding activity,high stability and mechanical robustness,Cu/N-C(FT)@500 monolith is promising as a low-cost,efficient and CO-resistant electrocatalyst for MOR. 展开更多
关键词 Copper nanocrystal methanol oxidation reaction Non-noble metal-based electrocatalysts Poison-resistant electrocatalysts Nitrogen-doped carbon
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Preparation of Surfactant-Free Pt and PtRu Nanoparticles with High Activity for Methanol Oxidation 被引量:1
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作者 Yao Yao Jun Cai +1 位作者 Yong-li Zheng Yan-xia Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期332-336,共5页
A simple and green approach to synthesize highly active electro-catalysts for methanol oxi- dation reaction (MOR) without using any organic agents is described. Pt nanoparticles are directly deposited on the pre-cle... A simple and green approach to synthesize highly active electro-catalysts for methanol oxi- dation reaction (MOR) without using any organic agents is described. Pt nanoparticles are directly deposited on the pre-cleaned and pre-oxidized multiwall carbon nanotubes (MWC- NTs) from Pt salt by using CO as the reductant. MOR activity has been characterized by both cyclic voltammetry and chronoamperometry, the current density and mass specific current at the peak potential (ca. 0.9 V vs. RHE) reaches 11.6 mA/cm^2 and 860 mA/mgpt, respectively. After electro-deposition of Ru onto the Pt/MWCNTs surface, the catalysts show steady state mass specific current of 20 and 80 mA/mgpt at 0.5 and 0.6 V, respectively. 展开更多
关键词 Pt nano-electrocatalyst PtRu nano-electrocatalyst Green synthesis methanol oxidation reaction Carbon monoxide
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AgAuPd/meso-Co_3O_4: High-performance catalysts for methanol oxidation 被引量:1
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作者 Jun Yang Yuxi Liu +4 位作者 Jiguang Deng Xingtian Zhao Kunfeng Zhang Zhuo Han Hongxing Dai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第6期837-848,共12页
The meso-Co3O4 and AgxAuyPd/meso-Co3O4 catalysts were prepared using the KIT-6-templating and polyvinyl alcohol-protected NaBH4 reduction methods,respectively.Various techniques were used to characterize physicochemic... The meso-Co3O4 and AgxAuyPd/meso-Co3O4 catalysts were prepared using the KIT-6-templating and polyvinyl alcohol-protected NaBH4 reduction methods,respectively.Various techniques were used to characterize physicochemical properties of these materials.Catalytic performance of the samples was evaluated for methanol combustion.The cubically crystallized Co3O4 support displayed a three-dimensionally ordered mesoporous structure.The supported noble metal nanoparticles(NPs)possessed a surface area of 115.125 m^2/g,with the noble NPs(average size=2.8.4.5 nm)being uniformly dispersed on the surface of meso-Co3O4.Among all of the samples,0.68 wt%Ag0.75Au1.14Pd/meso-Co3O4 showed the highest catalytic activity(T50%=100℃and T90%=112℃at a space velocity of 80000 mL(g^–1 h^–1).The partial deactivation of the 0.68 wt%Ag0.75Au1.14Pd/meso-Co3O4 sample due to water vapor or carbon dioxide introduction was reversible.It is concluded that the good catalytic performance of 0.68 wt%Ag0.75Au1.14Pd/meso-Co3O4 was associated with its highly dispersed Ag0.75Au1.14Pd alloy NPs,high adsorbed oxygen species concentration,good low-temperature reducibility,and strong interaction between Ag0.75Au1.14Pd alloy NPs and meso-Co3O4. 展开更多
关键词 Volatile organic compound Mesoporous cobalt oxide Supported noble metal catalyst AgAuPd alloy nanoparticle methanol oxidation
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Preparation of MIL-88B(Fe_(x),Co_(1‒x))catalysts and their application in one-step liquid-phase methanol oxidation to methyl formate using H_(2)O_(2)
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作者 Jianfang Liu Zhenzhen Ran +1 位作者 Qiyan Cao Shengfu Ji 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第12期2254-2264,共11页
The selective oxidation of methanol to methyl formate is one of the most attractive processes to obtain value-added methanol-downstream products.The development of highly efficient and stable catalysts is critical for... The selective oxidation of methanol to methyl formate is one of the most attractive processes to obtain value-added methanol-downstream products.The development of highly efficient and stable catalysts is critical for this transformation.In this study,a series of MIL-88B(Fe_(x),Co_(1‒x))bimetallic catalysts with different Fe/Co molar ratios were prepared through a one-pot hydrothermal method.X-ray diffraction,scanning electron microscopy,high-resolution transmission electron microscopy,energy dispersive spectroscopy,Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,N2 adsorption-desorption,and inductively coupled plasma-mass spectrometry characterization were performed to elucidate the structure of the catalysts.The activity of the catalysts were assessed in the one-step oxidation of methanol to methyl formate with H_(2)O_(2)in a liquid-phase batch reactor.The results show that the MIL-88B(Fe_(x),Co_(1‒x))catalysts exhibit uniform needle-like morphologies with an average length and width of 400-600 nm and 100-150 nm,respectively.Co^(2+)is incorporated into the framework by partially replacing Fe^(3+)in MIL-88B.Moreover,the catalyst efficiently promoted the conversion of methanol to methyl formate.When MIL-88B(Fe_(0.7),Co_(0.3))catalyst was used with a molar ratio of H_(2)O_(2)to methanol of 0.5 at 80℃for 60 min,34.8%methanol conversion was achieved,and the selectivity toward methyl formate was 67.6%.The catalysts also showed great stability with a steady conversion and selectivity even after four cycles.The preliminary oxidation mechanism was also studied.It was determined that H_(2)O_(2)is first adsorbed on the Fe^(3+)sites and subsequently activates these sites.Methanol is adsorbed by the O atoms of the framework through hydrogen bonding and is gradually oxidized to formic acid.Subsequently,formic acid reacts with the residual methanol at the Fe^(3+)and Co^(2+)Lewis acid sites to form methyl formate. 展开更多
关键词 Bimetal-organic frameworks methanol oxidation Liquid phase One-step transformation Methyl formate
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