后合成静电吸附辅助制备高效Fe-N-C单原子氧还原催化剂用于锌-空气电池  

Post-synthetic electrostatic adsorption-assisted fabrication of efficient single-atom Fe-N-C oxygen reduction catalysts for Zn-air batteries

作　　者：李乐 李娜 夏佳伟 邢浩然 阿里夫·默罕默德 赵宜涛 何光裕 陈海群 Le Li;Na Li;Jiawei Xia;Haoran Xing;Muhammad Arif;Yitao Zhao;Guangyu He;Haiqun Chen(Key Laboratory of Advanced Catalytic Materials and Technology,Advanced Catalysis and Green Manufacturing Collaborative Innovation Center,Changzhou University,Changzhou 213164,China)

机构地区：[1]Key Laboratory of Advanced Catalytic Materials and Technology,Advanced Catalysis and Green Manufacturing Collaborative Innovation Center,Changzhou University,Changzhou 213164,China

出　　处：《Science China Materials》2023年第3期992-1001,共10页中国科学(材料科学(英文版)

基　　金：supported by the National Natural Science Foundation of China(22078028 and 21978026)。

摘　　要：设计和制备高效的非铂族催化剂对锌-空气电池的大规模应用至关重要.本文采用简单的后合成静电吸附策略制备了Fe-N-C单原子催化剂(Fe-SA/N-C).其中,Fe原子与相邻的氮原子形成Fe-N4活性位点并锚定在三维多孔碳上.该催化剂在0.1 mol L^(-1)KOH (E_(1/2)=0.92 V)和0.5 mol L^(-1)H_(2)SO_(4)(E_(1/2)=0.77 V)中均表现出优异的氧化还原活性,性能优于商业Pt/C催化剂(0.1 mol L^(-1)KOH,E_(1/2)=0.85 V;0.5 mol L^(-1)H_(2)SO_(4),E_(1/2)=0.79 V).此外,以Fe-SA/N-C作为阴极催化剂自组装的液体锌-空气电池具有优异的放电比容量和峰值功率密度,优于商业Pt/C催化剂.密度泛函理论计算结果表明,石墨化氮掺杂的Fe-N4位点能有效提高ORR中间产物的活化程度,降低速率决定步骤的能垒.本工作对非铂族催化剂的实验制备和理论研究提出了新的见解,为锌-空气电池中使用的非铂族催化剂的合理设计提供了一般策略.Highly efficient platinum-group metal(PGM)-free electrocatalysts are essential for the large-scale utilization of Zn-air batteries(ZABs). Herein, we report the simple fabrication of a single atomic PGM-free electrocatalyst, Fe-SA/NC, via a post-synthetic electrostatic absorption(PSEA) strategy. The single Fe atoms are anchored on the three-dimensiaonal(3D) porous carbon with adjacent N atoms,forming atomic Fe-N4 active sites. Fe-SA/N-C exhibits excellent ORR activity in 0.1 mol L^(-1)KOH aqueous solution(E_(1/2)= 0.92 V) and 0.5 mol L^(-1)H_(2)SO_(4)aqueous solution(E_(1/2) =0.77 V), superior to those of commercial Pt/C(0.85 and0.79 V, respectively). As a proof of concept, homemade liquid ZAB with Fe-SA/N-C catalyst displays outstanding discharging specific capacity and peak power density, outperforming the commercial Pt/C. According to the density functional theory calculation, the Fe-N4 sites with graphitic N dopant can improve the activation of intermediates and decrease the energy barrier of the rate-determining step. This work highlights new insights for the experimental and theoretical guidance of PGM-free electrocatalysts and prescribes a general strategy for the rational design of PGM-free electrocatalysts used in ZABs.

关 键 词：密度泛函理论计算 单原子催化剂 PT/C催化剂 静电吸附 氧化还原活性 能垒 活化程度 阴极催化剂 

分 类 号：TQ426[化学工程] TM911.41[电气工程—电力电子与电力传动]