Superstructured Carbon with Enhanced Kinetics for Zinc‐Air Battery and Self‐Powered Overall Water Splitting

Abstract The present study proposes a novel engineering concept for the customization of functionality and construction of superstructure to fabricate 2D monolayered N‐doped carbon superstructure electrocatalysts decorated with Co single atoms or Co ₂ P nanoparticles derived from 2D bimetallic ZnCo‐ZIF superstructure precursors. The hierarchically porous carbon superstructure maximizes the exposure of accessible active sites, enhances electron/mass transport efficiency, and accelerates reaction kinetics simultaneously. Consequently, the Co single atoms embedded N‐doped carbon superstructure (Co‐NCS) exhibits remarkable catalytic activity toward oxygen reduction reaction, achieving a half‐wave potential of 0.886 V versus RHE. Additionally, the Co ₂ P nanoparticles embedded N‐doped carbon superstructure (Co ₂ P‐NCS) demonstrates high activity for both oxygen evolution reaction and hydrogen evolution reaction, delivering low overpotentials of 292 mV at 10 mA cm ⁻² and 193 mV at 10 mA cm ⁻² respectively. Impressively, when employed in an assembled rechargeable Zn‐air battery, the as‐prepared 2D carbon superstructure electrocatalysts exhibit exceptional performance with a peak power density of 219 mW cm ⁻² and a minimal charge/discharge voltage gap of only 1.16 V at 100 mA cm ⁻² . Moreover, the cell voltage required to drive an overall water‐splitting electrolyzer at a current density of 10 mA cm ⁻² is merely 1.69 V using these catalysts as electrodes.