Electronic Tuning of SnS<sub>2</sub> Nanosheets by Hydrogen Incorporation for Efficient CO<sub>2</sub> Electroreduction
An Zhang, Yongxiang Liang, Huiping Li, Shilong Wang, Qixuan Chang, Kaiyue Peng, Zhigang Geng, Jie Zeng
Abstract
Surface functionalization with atoms serves as an important strategy to modulate the catalytic activities of low-dimensional nanomaterials. Herein, we developed a facile hydrogen incorporation strategy for improving the catalytic activities of SnS2 nanosheets toward CO2 electroreduction. Compared with SnS2 nanosheets, the hydrogen-incorporated SnS2 (denoted as H-SnS2) nanosheets exhibited high current density and Faradaic efficiency (FE) for formate. At −0.9 V vs RHE, H-SnS2 nanosheets displayed a maximum FE of 93% for carbonaceous product, which rivals the activities of most Sn-based catalysts in CO2 electroreduction. Mechanistic studies disclosed that the incorporation of surface hydrogen induced the electron injection into the structures of H-SnS2 nanosheets, which largely facilitates the process of CO2 activation. Density functional theory (DFT) calculations further revealed that hydrogen incorporation decreased the energy barrier for the formation of HCOO* intermediates, thus contributing to the CO2-to-formate conversion on H-SnS2 nanosheets.