Micro–meso-macroporous FeCo-N-C derived from hierarchical bimetallic FeCo-ZIFs as cathode catalysts for enhanced Li-O2 batteries performance

作     者：Fufang Chao Baoxing Wang Jiaojiao Ren Yingwei Lu Wenrui Zhang Xizhang Wang Lin Cheng Yongbing Lou Jinxi Chen Fufang Chao;Baoxing Wang;Jiaojiao Ren;Yingwei Lu;Wenrui Zhang;Xizhang Wang;Lin Cheng;Yongbing Lou;Jinxi Chen

作者机构：School of Chemistry and Chemical Engineering Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device Southeast UniversityNanjing 211189 Jiangsu China Key Laboratory of Mesoscopic Chemistry of MOE Jiangsu Provincial Lab for Nanotechnology School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093 Jiangsu China 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2019年第28卷第8期

页      面：212-219,I0008页

核心收录：

学科分类：0820[工学-石油与天然气工程] 0808[工学-电气工程] 081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术] 0807[工学-动力工程及工程热物理] 0827[工学-核科学与技术] 0703[理学-化学] 

基　　金：sponsored by the National Natural Science Foundation of China(21475021 and 21427807) the Fundamental Research Funds for the Central Universities(2242017 K41023) 

主　　题：Micro–meso-macroporous FeCo-N-C Li-O2 battery Cathode catalyst Oxygen evolution/reduction reaction 

摘      要：Developing bifunctional catalysts that increase both the OER and ORR kinetics and transport reactants with high efficiency is desirable. Herein, micro–meso-macroporous FeCo-N-C-X(denoted as MFeCo-N-C-X, X represents Fe/Co molar ratio in bimetallic zeolite imidazole frameworks FeCo-ZIFs) catalysts derived from hierarchical M-FeCo-ZIFs-X was prepared. The micropores in M-FeCo-N-C-X have strong capability in O2 capture as well as dictate the nucleation and early-stage deposition of Li2O2,the mesopores provided a channel for the electrolyte wetting, and the macroporous structure promoted more available active sites when used as cathode for Li-O2 batteries. More importantly, M-Fe CoN-C-0.2 based cathode showed a high initial capacity(18,750 mAh g-1@0.1 A g-1), good rate capability(7900 m Ah g-1@0.5 A g-1), and cycle stability up to 192 cycles. Interestingly, the FeCo-N-C-0.2 without macropores suffered relatively poorer stability with only 75 cycles, although its discharge capacity was still as high as 17,200 mA h g-1(@0.1 A g-1). The excellent performance attributed to the synergistic contribution of homogeneous Fe, Co nanoparticles and N co-doping carbon frameworks with special micro–meso-macroporous structure. The results showed that hierarchical FeCo-N-C architectures are promising cathode catalysts for Li-O2 batteries.