基于Ag三角纳米棱柱的AgPd和AgPt纳米合金的可控制备及其在燃料电池中的电催化应用

Currently, Pt and Pd are the most commonly used electrocatalysts in fuel cells (FCs). However, the scarce storage of noble metals, susceptibility to poisoning of Pt, fuel crossover and slow kinetics of oxygen reduction pose a severe challenge to the large-scale commercialization of FCs. In order to improve the utilization efficiency of Pt and Pd, and to enhance their electrocatalytic performances, this research project aims to design and synthesize AgPt and AgPd nanoalloys with different structures based on triangular Ag nanoprisms. By taking advantage of the structural features of Ag nanoprisms, choosing different synthetic methods and changing experimental parameters, the chemical composition, morphological structures, exposed facets and distribution of active sites of the nanoalloys could be effectively and rationally tailored. The electrocatalytic performances of the as-obtained nanoalloys will be evaluated and optimized, and the relationship between the electrocatalysis properties and structural features will be disclosed. The implementation of this project will be extendable to the design of novel nanoalloy electrocatalysts, and also be of great significance for the enhancement of electrocatalytic performances in fuel cells.

目前燃料电池中常用的电催化剂主要是铂 (Pt) 或钯 (Pd) 贵金属催化剂。然而，贵金属储量匮乏，Pt催化剂易中毒，燃料渗透以及缓慢的氧还原动力学等弊端极大地阻碍了燃料电池的大规模商业化应用。为了提高Pt和Pd的利用效率，同时提高Pt和Pd的催化活性，本项目拟以Ag三角纳米棱柱为模板，设计合成具有不同形貌结构的AgPt和AgPd纳米合金。充分利用Ag三角纳米棱柱的结构特点，通过不同合成方法，改变实验参数，实现对合金的化学组分、形貌结构、暴露晶面和位点分布的有效调控。考察并优化合金催化剂在燃料电池催化中的性能，总结形貌结构与电催化活性之间的关系。本项目的实施为设计新型合金催化剂提供合成方法，同时对提高燃料电池的催化性能具有十分重要的实践意义。

目前燃料电池中常用的电催化剂主要是铂（Pt）或钯（Pd）贵金属催化剂。然而，贵金属储量匮乏，Pt催化剂易中毒，燃料渗透以及缓慢的氧还原动力学等弊端极大地阻碍了燃料电池的大规模商业化应用。为了提高Pt和Pd的利用效率，同时提高Pt和Pd的催化活性，本项目通过结构设计和组分调控，合成了一系列具有不用组分和形貌的贵金属基电催化剂。采用不同合成策略，改变实验参数，实现对合金催化剂的化学组分、形貌结构、暴露晶面和位点分布的有效调控。考察并优化合金催化剂在燃料电池催化中的性能，总结形貌结构与电催化活性之间的关系。为了进一步降低催化剂的价格，寻求价格低廉但性能优异的催化剂，本项目还合成了一系列非贵金属基的电催化剂，如过渡金属氧化物/碳纳米纤维复合材料、Fe单原子催化剂和Ni3Fe纳米粒子/碳纳米纤维复合材料等，它们在电催化氧气还原反应、氢气析出反应和金属—空气电池中展现出良好的催化活性和稳定性。本项目的实施为设计新型高性能电催化剂提供合成思路，对提高燃料电池电催化剂的催化性能具有十分重要的实践意义。