Vacancy engineering of two-dimensional W 2 N 3 nanosheets for efficient CO 2 hydrogenation.

Peaking carbon emissions and achieving carbon neutrality have become the consensus goal of the international community to solve the environmental problems threatening mankind caused by accumulative greenhouse gases like CO 2 . Herein we proposed vacancy engineering of two-dimensional (2D) topological W 2 N 3 for efficient CO 2 hydrogenation into high value-added chemicals and fuels. Spherical aberration corrected scanning transmission electron microscopy (Cs-corrected STEM) confirmed a large amount of N vacancies on the catalyst surface, which significantly reduced the energy barrier for the formation of the essential intermediates of *CO and *CHO as revealed by density functional theory (DFT) calculations. Consequently, the highly stable catalyst exhibited efficient CO 2 hydrogenation superior to many previous reports with a maximum CO 2 conversion rate of 24% and a high selectivity of 23% for C 2+ hydrocarbons. This work provided not only insight into the vacancy-controlled CO 2 hydrogenation mechanism, but also fresh ammunition to bring the remaining potential of 2D topological transition metal nitrides in the field of catalysis.