Silicalite-1 Zeolites-Supported Copper Oxides for CO ₂ Electroreduction in Acidic Media

Electrochemical CO 2 reduction reaction (CO 2 R) in acidic media represents a promising route to CO 2 utilization by circumventing the critical concern of carbonate formation in water. Herein, we report that silicalite-1 (S-1) zeolites functioned as a solid support for copper oxides (CuO), which demonstrated superior performance in electrochemical CO 2 conversion into hydrocarbons in acidic media. The as-derived catalyst achieved a Faradaic efficiency (FE) above 40% for the production of CH 4 and C 2 H 4 at relatively high overpotentials. Systematic control experiments revealed that the microporosity of S-1 zeolite concentrated CO 2 through its high physical adsorption ability, while the silica surface stabilized the Cu oxidation state against an extreme reduction environment. Such effects enabled selective and durable CO 2 conversion. These results underscore the potential of microporous zeolites as an efficient support for designing high-performance CO 2 R electrocatalysts.