单原子铂/金属氮化物/氮掺杂石墨烯二维三层结构电催化剂的构筑及其多活性位催化增强效应研究

To overcome the problems of low platinum electrocatalyst of alcohol fuel cell, such as few active sites, poor stability, weak CO resistance, low oxygen reduction efficiency and so on, this project will introduce single-atom Pt as active subject, and design of single-atom Pt/metal nitride/N doped graphene two-dimensional three-layer structure catalyst from two angles of multiple active sites superposition and simple preparation of graphene based catalyst. This structural catalyst is not only highly stable and highly conductive, but also has multiple types of high density active sites. Accordingly, it is expected that the excellent electrocatalytic performances of alcohol oxidation and oxygen reduction can be achieved, respectively, by adjusting the type of metal nitride in the catalyst. This project will focus on the construction of the two-dimensional three-layer structure of the catalyst, and explore the dependencies of structure-composition-performance. Alcohol oxidation and oxygen reduction are used as catalytic models, respectively, and the catalytic activity, CO tolerance ability and durability are systematically studied. Based on density functional theory calculation, enhancement mechanism on electrocatalytic activity due to the combination of multi-type active sites will be systematical expatiation. The catalytic performance of the catalyst would be further improved, in order to promote the practical application of low platinum catalyst in alcohol fuel cell.

本项目针对醇类燃料电池低铂催化剂存在的活性位少、稳定性差、抗毒性弱、氧还原效率低等问题，拟引入单原子铂作为催化剂活性主体，从多活性位叠加和简单工艺制备石墨烯基催化剂两个角度出发，设计单原子铂/金属氮化物/氮掺杂石墨烯二维三层结构催化剂。该结构催化剂不仅具有高稳定性和高电导，同时拥有多类型的高密度活性位点。由此预计通过调节该类催化剂中金属氮化物的类型，能够分别实现优异的醇氧化和氧还原电催化性能。项目将重点研究催化剂的二维三层结构的构筑方法，探索其结构-组成-性能的依赖关系。分别以醇氧化和氧还原为催化模型，系统研究催化剂的催化活性、抗毒性和耐久性等性能；并结合密度泛函理论计算，系统阐述多类型活性位点组合对电催化性能的增强机制；进一步提升该催化剂的电催化性能，推进低铂电催化剂在醇类燃料电池上的实际应用。

针对醇类燃料电池低铂催化剂存在的活性位少、稳定性差、抗毒性弱、氧还原效率低等问题，本项目设计合成了铂纳米颗粒/金属氮化物/氮掺杂石墨烯二维三层结构电催化剂，通过Pt、过渡金属氮化物、N掺杂石墨烯等活性位的叠加效应提高催化剂的导电性、稳定性和催化活性。并通过调节金属氮化物的类型（TiN，Nb4N5,TaON），分别实现了优异的醇氧化和氧还原电催化性能。项目重点研究了催化剂的二维三层结构的构筑方法，探索了其结构-组成-性能的依赖关系。并分别以醇氧化和氧还原为催化模型，系统研究了催化剂的催化活性、抗毒性、耐久性和选择性等性能；并结合密度泛函理论计算，阐述了多类型活性位点组合对电催化性能的增强机制。