碳载金属单原子催化剂

摘要

Metal single atom catalysts (SACs) have been attracting increasing attention in recent years owing to their incredible performance in several key catalytic reactions such as the oxygen reduction reaction and CO oxidation.The construction of well dispersed stable SACs can not only make it possible to understand the catalytic reactions on the atomic scale,but is also important for developing novel industrial catalysts.Recent efforts have been focused on dispersing metal SACs on carbon substrates rather than on metals or metal oxides for improved catalytic behavior.Especially,graphene-based materials have proven to be excellent candidates for supporting SACs due to their unique structural and electronic properties.Nevertheless,the anchoring mechanism between metal SACs and carbon substrates is not well understood.Here we review the many roles of carbon materials as the support of SACs and highlight the anchoring mechanism.We also propose some suggestions to improve the experimental and theoretical research methods to expand the number of applications and realize industrial applications.%金属单原子催化剂由于在氧还原反应和CO氧化反应等关键催化反应中表现出优异的性能而备受关注.构建高分散性金属单原子催化剂体系有助于从原子尺度认识催化反应,发现催化新机理,进而推进新型工业催化剂的开发.最新研究表明,利用炭材料替代金属或金属氧化物载体,可以有效提高金属单原子催化剂的催化性能,石墨烯独特的结构和电子特性使其成为单原子催化剂的优良载体.然而,对于金属单原子催化剂和碳载体之间的钉扎机理以及金属单一活性位点的作用机理还有待进一步阐明.本文总结了炭材料作为金属单原子载体的多重作用,特别是石墨烯晶格缺陷对金属单原子的钉扎机制;同时,对改进实验和理论研究方法,以及扩展应用范围和实现工业化应用提出了建议与展望.