Heterogeneous Structure of Sn/SnO2 Constructed via Phase Engineering for Efficient and Stable CO2 Reduction.

Abstract

The electrochemical carbon dioxide reduction reaction (CO2RR) catalyzed by Sn-based materials shows great potential for CO2-to-formate conversion. The presence of tin species with different oxidation states can promote the catalytic performance, most likely due to the interfaces of metallic and oxide phases that induce a synergistic effect. Therefore, it is desirable yet challenging to synthesize a hybrid catalyst with abundant active heterogeneous interfaces. Herein, we synthesize a hybrid catalyst constructed by decorating nanosized SnS2 in the SnO2 matrix. The uniformly distributed SnS2 nanoparticles are first reduced to metallic tin, which assists in the generation of abundant Sn/SnO2 heterogeneous interfaces under the in situ reduction process. Because of the electronic modulation at the heterogeneous interfaces, the resulting catalyst delivers a high current density of 200 mA·cm-2 at -0.86 V vs RHE, and the performance is stable for over 20 h. This work suggests a potentially powerful interface engineering strategy for the development of high-performance electrocatalysts for the CO2RR.