In-plane heterostructured Ag2S-In2S3 atomic layers enabling boosted CO2 photoreduction into CH4
Weiwei Shao, Shumin Wang, Juncheng Zhu, Xiaodong Li, Xingchen Jiao, Yang Pan, Yongfu Sun, Yi Xie
Abstract
Sluggish separation and migration kinetics of the photogenerated carriers account for the low-efficiency of CO2 photoreduction into CH4. Design and construction two-dimensional (2D) in-plane heterostructures demonstrate to be an appealing approach to address above obstacles. Herein, we fabricate 2D in-plane heterostructured Ag2S-In2S3 atomic layers via an ion-exchange strategy. Photoluminescence spectra, time-resolved photoluminescence spectra, and photoelectrochemical measurements firmly affirm the optimized carrier dynamics of the In2S3 atomic layers after the introduction of in-plane heterostructure. In-situ Fourier transform infrared spectroscopy spectra and density functional theory (DFT) calculations disclose the in-plane heterostructure contributes to CO2 activation and modulates the adsorption strength of CO* intermediates to facilitate the formation of CHO* intermediates, which are further protonated to CH4. In consequence, the in-plane heterostructure achieves the CH4 evolution rate of 20 µmol·g−1·h−1, about 16.7 times higher than that of the In2S3 atomic layers. In short, this work proves construction of in-plane heterostructures as a promising method for obtaining high-efficiency CO2-to-CH4 photoconversion properties.