Interfaces Engineering of Ultrafine Ni@Ni₂P/C Core–Shell Heterostructure for High Yield Hydrogen Peroxide Electrosynthesis

AbstractDeveloping cost‐effective and sustainable catalysts with exceptional activity and selectivity is essential for the practical implementation of on‐site H2O2 electrosynthesis, yet it remains a formidable challenge. Metal phosphide core–shell heterostructures anchored in carbon nanosheets (denoted as Ni@Ni2P/C NSs) are designed and synthesized via carbonization and phosphidation of the 2D Ni‐BDC precursor. This core–shell nanostructure provides more accessible active sites and enhanced durability, while the 2D carbon nanosheet substrate prevents heterostructure aggregation and facilitates mass transfer. Theoretical calculations further reveal that the Ni/Ni2P heterostructure‐induced optimization of geometric and electronic structures enables the favored adsorption of OOH* intermediate. All these features endow the Ni@Ni2P/C NSs with remarkable performance in 2e ORR for H2O2 synthesis, achieving a top yield rate of 95.6 mg L−1 h−1 with both selectivity and Faradaic efficiency exceeding 90% under a wide range of applied potentials. Furthermore, when utilized as the anode of an assembled gas diffusion electrode (GDE) device, the Ni@Ni2P/C NSs achieve in situ H2O2 production with excellent long‐term durability (>32 h). Evidently, this work provides a unique insight into the origin of 2e ORR and proposes optimization of H2O2 production through nano‐interface manipulation.