Topological Transformation Constructed c-SnO2/a-ZnSnO3 Heterostructure with Abundant Interfaces for Efficient Electrocatalytic CO2 Reduction

Abstract

It is of great significance to construction of catalysts with abundant active sites and efficient electron transfer property for CO₂ reduction reaction (CO2RR). In this work, a crystalline tin oxide (SnO2)/amorphous zinc metastannate (ZnSnO3) (c-SnO2/a-ZnSnO3) heterostructure has been developed through topotactic transformation under post-annealing. The c-SnO2/a-ZnSnO3 heterostructure with abundant and robust interfaces has been validated as an efficacious catalyst for the electrocatalytic CO2RR to C1 products (formate and CO). Through a series of structural analysis, electrochemical tests and in-situ characterization, the enhanced electrocatalytic performance of the c-SnO2/a-ZnSnO3 heterostructure can be ascribed from the following factors: 1) The unique c-SnO2/a-ZnSnO3 heterostructure provide large numbers of unsaturated active sites, facilitating the adsorption and reduction of CO2 and intermediates. 2) The abundant and robust crystalline/amorphous interfaces as well as the optimized electronic structure improve the PCET process, thus promoting the CO2RR performance.