Interfacial Modulation of Composite Structures for Activating Ag ₃ PO ₄ Toward Efficient and Stable Electrocatalytic Ethylene Epoxidation

The development of efficient and stable electrocatalysts represents a pivotal challenge in realizing a green process for the direct electrocatalytic epoxidation of ethylene. This study addresses the limitations of silver phosphate (Ag 3 PO 4 ), a material with promising catalytic activity that is hindered by intrinsically low electrical conductivity and structural instability. Through an interface engineering strategy, we design and synthesize a composite catalyst of Ag 3 PO 4 encapsulated by graphene oxide (GO), denoted as Ag 3 PO 4 @GO. In this composite structure, GO not only acts as a conductive scaffold that significantly enhances charge transfer efficiency but also effectively suppresses the agglomeration of Ag 3 PO 4 nanoparticles via an interfacial anchoring effect. Systematic characterization confirms a significant electronic interaction between GO and Ag 3 PO 4 , which optimizes the electronic structure of the active sites. Electrocatalytic performance tests demonstrate that the Ag 3 PO 4 @GO catalyst achieves an ethylene oxide production rate of 98 μmol·cm −2 ·h −1 with a Faradaic efficiency (FE) of 35% at 1.85 V (vs. RHE), along with excellent operational stability for over 10 h. This work, by designing a multifunctional support, simultaneously mitigates the inherent conductivity and stability issues of Ag 3 PO 4 catalysts, thereby offering a new avenue for developing high‐performance electrocatalysts for olefin epoxidation.