Vacancy engineering of two-dimensional W2N3 nanosheets for efficient CO2 hydrogenation

Abstract

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 CO₂. Herein we proposed vacancy engineering of two-dimensional (2D) topological W₂N₃ for efficient CO₂ 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 CO₂ hydrogenation superior to many previous reports with a maximum CO₂ conversion rate of 24% and a high selectivity of 23% for C₂₊ hydrocarbons. This work provided not only insight into the vacancy-controlled CO₂ hydrogenation mechanism, but also fresh ammunition to bring the remaining potential of 2D topological transition metal nitrides in the field of catalysis.