Surface Reorganization on Electrochemically‐Induced Zn–Ni–Co Spinel Oxides for Enhanced Oxygen Electrocatalysis
Xiao‐Tong Wang, Ting Ouyang, Ling Wang, Jia‐Huan Zhong, Zhao‐Qing Liu
Abstract
Abstract Herein, we highlight redox‐inert Zn 2+ in spinel‐type oxide (Zn X Ni 1− X Co 2 O 4 ) to synergistically optimize physical pore structure and increase the formation of active species on the catalyst surface. The presence of Zn 2+ segregation has been identified experimentally and theoretically under oxygen‐evolving condition, the newly formed V Zn −O−Co allows more suitable binding interaction between the active center Co and the oxygenated species, resulting in superior ORR performance. Moreover, a liquid flow Zn–air battery is constituted employing the structurally optimized Zn 0.4 Ni 0.6 Co 2 O 4 nanoparticles supported on N‐doped carbon nanotube (ZNCO/NCNTs) as an efficient air cathode, which presents remarkable power density (109.1 mW cm −2 ), high open circuit potential (1.48 V vs. Zn), excellent durability, and high‐rate performance. This finding could elucidate the experimentally observed enhancement in the ORR activity of Zn X Ni 1− X Co 2 O 4 oxides after the OER test.