Confined‐Assembled FeNi Alloy‐Embedded Porous Carbon Nanosheet Reactors as Efficient Bifunctional Electrocatalysts for Rechargeable Zinc‐Air Batteries

Highly dispersed metallic active centers supported on two-dimensional conductive carbon materials hold great promise for energy-conversion applications; however, their structurally controllable synthesis remains challenging. Herein, we propose a template-assisted assembly strategy using ZnO as a structure-directing template to construct a branched porous carbon framework embedded with FeNi alloy species. Unlike conventional hard templates that merely create pores, the ZnO template creates a favorable microenvironment for CNT growth and simultaneously generates abundant mesopores upon its removal. Through coordination interactions between folic acid and Fe/Ni ions, two-dimensional confined precursors are first formed. This branched architecture, conceptually described as a porous carbon reactor, integrates a high specific surface area, efficient electron/ion transport pathways, and densely distributed catalytic active sites. As a result, the optimized catalyst exhibits excellent bifunctional ORR/OER activity in alkaline media, with a small potential gap (ΔE = 0.67 V). The assembled rechargeable zinc-air battery delivers a high peak power density of 239 mW cm$^{–2}$ together with outstanding cycling stability (over 200 h). ... mehrThis work provides a new paradigm for designing noble-metal-free electrocatalysts through template-guided assembly.