Band alignment in Zn2SnO4/SnO2 heterostructure enabling efficient CO2 electrochemical reduction

Abstract Engineering heterojunction is an underlying strategy to develop remarkable electrocatalysts for carbon dioxide (CO2) reduction due to its ability to tune electronic properties by interfacial cooperation. Herein, we report a novel type of cube-like Zn2SnO4/SnO2 heterostructure catalyst for CO2 reduction through a simple co-precipitation process. The high-quality heterostructures with band alignment promote interfacial charge transfer from Zn2SnO4 to SnO2, achieving the electronic modulation of Zn2SnO4/SnO2 for reducing the kinetic barriers of CO2 reduction. Density functional theory further reveals that Zn2SnO4/SnO2 allows HCOO* intermediate favorably stabilizing on its surface through improved hydrogen coverage effect comparing to pure Zn2SnO4 or SnO2. The hybrid catalyst presents satisfactory CO2 reduction properties with a stable HCOOH selectivity of 77% during 24 h at −1.08 V vs. RHE. This study provides a new heterostructure modeling and general methodology for electronic modulation and electrocatalysts development for high-performance CO2 reduction.