Multidimensional In2O3/In2S3 heterojunction with lattice distortion for CO2 photoconversion

Abstract

Photocatalytic CO2 reduction to sustainably product of fuels is a potential route to achieve clean energy conversion. Unfortunately, the sluggish charge transport dynamics and poor CO2 activation performance result in a low CO2 conversion efficiency. Herein, we develop a multidimensional In2O3/In2S3 (IO/IS) heterojunction with abundant lattice distortion structure and high concentration of oxygen defects. The close contact interfaces between the junction of the two phases ensure undisturbed transmission of electrons with high-speed. The increased free electron concentration promotes the adsorption and activation of CO2 on the catalyst surface, leaving the key intermediate *COOH at a lower energy barrier. The perfect combination of the band matching oxide and sulfide effectively reduces the internal energy barrier of the CO2 reduction reaction. Furthermore, the lattice distortion structure not only provides additional active sites, but also optimizes the kinetics of the reaction through microstructural regulation. Remarkably, the optimal IO/IS heterojunction exhibits superior CO2 reduction performance with CO evolution rate of 12.22 μmol g−1 h−1, achieving about 4 times compared to that of In2O3 and In2S3, respectively. This work emphasizes the importance of tight interfaces of heterojunction in improving the performance of CO2 photoreduction, and provides an effective strategy for construction of heterojunction photocatalysts.