Electrochemical epoxidation enhanced by C2H4 activation and hydroxyl generation at the Ag/SnO2 interface
Hao Dong, Ran Luo, Gong Zhang, Lulu Li, Chaoxi Wang, Guodong Sun, Hongyi Wang, Jiachang Liu, Tuo Wang, Zhi‐Jian Zhao, Peng Zhang, Jinlong Gong
Abstract
Direct electrochemical ethylene (C2H4) epoxidation with water (H2O) represents a promising approach for the production of value-added ethylene oxide (EO) in a sustainable way. However, the activity remains limited due to the sluggish activation of C2H4 and the stiff formation of *OH intermediate. This paper describes the design of a Ag/SnO2 electrocatalyst to achieve efficient electrochemical C2H4 epoxidation with a high faradaic efficiency of 39.4% for EO and a high selectivity of 91.5% at 25 mA/cm2 in a membrane electrode assembly. Results of in situ attenuated total reflection infrared spectra characterizations and computational calculations reveal that the Ag/SnO2 interface promotes C2H4 adsorption and activation to obtain *C2H4. Moreover, electrophilic *OH is generated on the catalyst surface through H2O dissociation, which further reacts with *C2H4 to facilitate the formation of *C2H4OH, contributing to the enhanced electrochemical epoxidation activity. This work would provide general guidance for designing catalysts for electrochemical olefin epoxidation through interface engineering. Electrochemical epoxidation by water is mainly hindered by the sluggish activation of C2H4 and the stiff formation of *OH intermediate. Here, the authors report an Ag/SnO2 interface to promote C2H4 adsorption and electrophilic *OH generation, leading to promoted production of ethylene oxide.