标题：Hierarchical peony-like FeCo-NC with conductive network and highly active sites as efficient electrocatalyst for rechargeable Zn-air battery
作者：Wang, Yiyan; Kumar, Anuj; Ma, Mang; Jia, Yin; Wang, Yu; Zhang, Ying; Zhang, Guoxin; Sun, Xiaoming; Yan, Zifeng
作者机构：[Wang, Yiyan; Ma, Mang; Wang, Yu; Zhang, Ying; Sun, Xiaoming; Yan, Zifeng] China Univ Petr East China, State Key Lab Heavy Oil Proc, Qingdao 266580, P 更多
通讯作者地址：Yan, ZF (corresponding author), China Univ Petr East China, State Key Lab Heavy Oil Proc, Qingdao 266580, Peoples R China.; Zhang, GX (corresponding a 更多
关键词：atomically dispersed catalyst; hierarchical structure; carbon nanotube;; oxygen electrocatalyst; rechargeable zinc-air battery
摘要：Carbon materials featuring hierarchical pores and atomically dispersed metal sites are promising catalysts for energy storage and conversion applications. Herein, we developed a facile strategy to construct functional carbon materials with a fluffy peony-like structure and dense binary FeCo-N-x active sites (termed as f-FeCo-CNT). By regulating the metal content in precursors, a three-dimensional (3D) interconnected conductive carbon nanotubes network was in-situ formed throughout the atomically dispersed FeCo-NC matrix during pyrolysis. Taking advantage of rich pore hierarchy and co-existence of highly active FeCo-N-x sites and beneficial FeCo alloy nanoparticles, the f-FeCo-CNT material exhibited excellent bifunctional performance towards oxygen reduction reaction/oxygen evolution reactions (ORR/OER) with respect to the atomically dispersed FeCo-NC (SA-f-FeCo-NC) and commercial Pt/C+RuO2 mixture, surpassing the SA-f-FeCo-NC with a 20 mV higher ORR half-wave potential and a 100 mV lower OER overpotential (at 10.0 mA/cm(2)). Remarkably, the f-FeCo-CNT-assembled Zn-air battery (ZAB) possessed a maximum specific power of 195.8 mW/cm(2), excellent rate capability, and very good cycling stability at large current density of 20.0 mA/cm(2). This work provides a facile and feasible synthetic strategy of constructing low-cost cathode materials with excellent comprehensive ZAB performance.