Universal Interface Metal Imprinting for Surface‐Selective Synthesis of Mesoporous Nitrogen‐Doped Carbon Supported Single‐Atom Catalysts

ABSTRACT Metal aggregation and insufficient site exposure are common issues in fabricating metal‐nitrogen‐carbon single‐atom catalysts (SACs). Herein, a universal interface metal imprinting (IMI) strategy is proposed for surface‐selective synthesis of nitrogen‐doped ordered mesoporous carbon (NOMC) supported SACs. It involves constructing an intimate and full‐coverage interface between a metal‐atom‐doped template (typically Fe‐doped SBA‐15) and a nanocast N‐doped carbon, followed by metal migration from the template framework to the interface and imprinting onto the N‐doped carbon surface. Density Functional Theory calculations and characterizations confirm the IMI process's thermodynamic feasibility and high efficiency. The resulting NOMC supported Fe SAC (Fe surf ‐NOMC) features ordered mesoporosity, high site density (1.71 × 10 19 sites g −1 ), and excellent surface exposure. It exhibits superb oxygen reduction reaction performance with a half‐wave potential of 0.92 V, a turnover frequency of 4.31 e site −1 s −1 , and a high stability, outperforming counterparts prepared by co‐nanocasting and post‐loading. The aqueous zinc‐air battery using Fe surf ‐NOMC as the cathode shows excellent performance with a peak power density of 194.7 mW cm −2 and a specific capacity of 807.8 mAh g Zn −1 . The IMI strategy is applicable to different templates and metals, providing a platform for fabricating ordered or disordered mesoporous surface‐enriched SACs.