阴离子化合物Y5Si3衬底增强石墨烯氧还原反应的第一性原理研究（英文）

Enhanced Oxygen Reduction on Graphene via Y5Si3 Electride Substrate:a First-Principles Study

本文采用阴离子化合物Y5Si3作为衬底,可以和石墨烯组成有效的氧还原催化剂.反应热计算结果表明,阴离子材料可以促进氧还原反应中的决速步-氧气质子化的过程,从而增强石墨烯的氧还原能力.电子结构计算表明体系较低的功函数(3.5eV),良好的导电性以及从衬底到石墨烯的电荷转移都可以促进石墨烯的氧还原催化能力.

Manipulating the chemical reactivity of graphene toward oxygen reduced reduction(ORR)is of particular interest for both fundamental research and practical application in fuel cell.Deposing graphene on selected substrate provides a structure-intact strategy to enhance its chemical reactivity due to substrate-induced charge and interface effect.Here,we report the graphene deposited on one-dimensional electride Y5Si3 as an effective ORR catalyst in acidic media.Thermodynamic calculations suggest that depositing graphene on electride materials can facilitate the protonation of O2,which is the rate-determining step based on the four-electron reaction pathway and thus promote the ORR activity.Further electronic calculations reveal that low work function(3.5 eV),superior electrical conductivity and slight charge transfer from substrate to graphene result in the enhanced ORR performance of graphene.These findings shed light on the rational design of ORR catalysts based on graphitic materials and emphasize the critical role of substrates for energy-related electrochemical reactions.