摘要
The Pt-based catalyst tends to be poisoned by carbon monoxide(CO)-like intermediates produced in fuel cell reactions,which seriously deteriorates its catalytic performance.Herein,noble metal Au with the capacity of resistance to CO-like intermediates poisoning was employed to construct multi-element Pt-based catalysts.Two trimetallic NiPtAu hollow nanocrystals(HNCs)with different surface Au contents were synthesized to explore the role of Au in electrocatalysis for alkaline methanol oxidation reaction(MOR).The trimetallic NiPtAu-SRAu HNCs catalyst with the relative rich Au content(15.17 at%)on surface exhibits a much lower CO oxidation peak potential than the other HNCs counterpart and 20 wt%Pt/C,which indicates the more exceptional CO-resisting performance.Besides,the MOR specific activity of NiPtAu-SRAu HNCs(31.52 mA cm^−2)is 7 times higher than that of 20wt%Pt/C(4.50 mA cm^−2).This enhancement in catalytic activity as well as anti-CO poisoning capability for NiPtAu-SRAu HNCs can be mainly ascribed to the weakened CO adsorption due to the exposure of Au atoms on NiPt surface evidenced by the experimental data and density functional theory calculations.This study not only investigates the role of Au in MOR catalysis but also could be helpful for designing and optimizing the electrocatalysts for high-active and robust fuel cell applications.
甲醇氧化反应中产生的CO等中间体是导致Pt基催化剂中毒而丧失催化活性的重要原因.针对该问题,本文利用具有较强抗CO中毒能力的贵金属Au构建多元Pt基催化剂.采用置换法合成了两种表面Au元素含量不同的NiPtAu中空纳米晶体(HNCs),分析了其电催化性能及抗CO毒化性能,并探讨了Au在电催化碱性甲醇氧化反应中的作用.研究结果表明,相比于其他样品,表面Au含量相对较高的NiPtAu-SRAuHNCs(15.17 at%)展现出更优异的电催化性能以及抗CO毒化性能.NiPt表面暴露的Au能削弱催化剂表面对CO的吸附,有利于提高电催化甲醇氧化的性能和抗CO中毒能力.这一研究结果不仅有助于深化认识Au在电催化甲醇氧化反应中的作用机理,同时也为燃料电池用新型高性能电催化剂的结构设计和优化提供了参考.
作者
Chang Liu
Zelin Chen
Dewei Rao
Jinfeng Zhang
Yunwei Liu
Yanan Chen
Yida Deng
Wenbin Hu
刘畅;陈泽霖;饶德伟;张金凤;刘赟威;陈亚楠;邓意达;胡文彬(School of Materials Science and Engineering,Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education,Tianjin Key Laboratory of Composite and Functional Materials,Tianjin University,Tianjin,300372,China;School of Materials Science and Engineering,Jiangsu University,Zhenjiang,212013,China;Joint School of National University of Singapore and Tianjin University,International Campus of Tianjin University,Fuzhou,350207,China)
基金
the National Natural Science Foundation of China(91963113,51701139,51671143 and U1601216)。
