Enhancing CO2 electroreduction performance by regulating interfacial structure of Ag/Zn(OH)F-derived catalysts

The electrocatalytic CO 2 reduction reaction to CO (ECO 2 RR) is an effective way to achieve carbon resource utilization. It requires catalysts that can synergistically couple CO 2 activation with efficient CO desorption. This work engineers this synergy by constructing an interfacial Ag δ+ -O-Zn configuration on Zn(OH)F-derived supports via controlled Ag loading (0–5 wt%). The optimal catalyst (3A/Z, 3 wt% Ag) balances the formation of interfacial, oxidized Ag species (Ag δ+ ) with well-dispersed metallic Ag 0 nanoparticles. It achieves a CO Faradaic efficiency of 95.4% at −1.15 V vs. RHE and maintains 86% efficiency over 5 h at 6.38 mA cm −2 . In-situ ATR-SEIRAS spectra and kinetics reveal that Ag δ+ -related sites lower the barrier for *COOH formation, while adjacent Ag 0 domains facilitate *CO desorption. Excessive loading (5A/Z) promotes Ag aggregation and support decomposition, diminishing the critical Ag δ+ -O-Zn interface and performance. This study highlights interface coordination engineering as a key strategy for designing bifunctional ECO 2 RR catalysts.