<i>P</i>‐Orbital Bismuth Single‐Atom Catalyst for Highly Effective Oxygen Electroreduction in Quasi‐Solid Zinc‐Air Batteries
Daijie Deng, Suqin Wu, Henan Li, Huaming Li, Li Xu
Abstract
Abstract P ‐block metals have gradually been utilized to synthesize non‐noble‐metal catalysts for oxygen reduction reaction (ORR) due to the easily tunable localized p ‐orbitals and resulted versatile electronic structures. The high‐density single‐atom bismuth sites (Bi−NC) anchored onto nitrogen‐doped three‐dimensional porous carbon are proved to possess significant electrocatalytic ORR performance. Theoretical calculations unveil positively charged bismuth centers prominently improved the adsorption capacity of N‐doped carbon to O 2 . The p orbitals of Bi sites within Bi−NC easily generate hybrid states with p orbitals of O 2 , thus promoting charge transfer and ultimately reducing the energy barrier of ORR. Benefiting from p ‐orbital electrons regulation of bismuth atoms, Bi−NC exhibit ORR half‐wave potential of 0.86 V (vs RHE). Additionally, both liquid and quasi‐solid zinc‐air batteries with Bi−NC as air‐cathodes achieve higher power density and specific capacity than 20 wt% Pt/C, and comparable stability and round‐trip efficiency with 20 wt% Pt/C. The discovery sheds light on the theoretical and practical guidance for p ‐block metallic single‐atom catalysts.