Sn Nanoclusters Confined in COP‐Derived Carbon for Catalytic Oxygen Reduction Reaction

Abstract The development of catalysts composed of single atoms is crucial for enhancing the performance of oxygen reduction reaction (ORR). However, the unsatisfactory intrinsic activity of these catalysts still poses a major challenge, limiting their overall effectiveness. One approach to addressing this challenge is the introduction of metal clusters, which can form a synergistic effect with the single atoms, ultimately improving their performance. In this study, core‐shell structured carbon polymer is constructed with Zn atoms and Sn nanoclusters by directly subjecting pyrolysis of the covalent organic polymer (COP) and metal organic framework (MOF) (COP@MOF). The thin COP shell serves a dual purpose: it prevents the collapse and aggregation of zeolitic imidazolate framework‐8 (ZIF‐8) and promotes the formation of mesopores, facilitating mass transport and enhancing the graphitization degree to improve conductivity. The resulting Sn‐COP@MOF₈₀₀ exhibits promising catalytic performance in the ORR, demonstrating a half‐wave potential of 0.81 V and current density of 5.56 mA cm⁻² in 0.1 m KOH, which is comparable to that of Pt/C. This study provides new ideas for exploring the application of metal single atoms and metal nanoclusters in ORR catalysis through synergistic effects.