Efficient photoreduction of carbon dioxide to ethanol using diatomic nitrogen-doped black phosphorus

Successful conversion of CO₂ into C₂ products requires the development of new catalysts that overcome the difficulties in efficient light harvesting and CO-CO coupling. Herein, density functional theory (DFT) is used to assess the photoreduction properties of nitrogen-doped black phosphorus. The geometric structure, redox potential, first step of hydrogenation activation, CO desorption, and CO-CO coupling are systematically calculated, based on which the diatomic nitrogen-doped black phosphorus (N₂@BP_V) stands out. The calculated results of the CO₂RR pathway demonstrate that N₂@BP_V has excellent selectivity and high activity for CH₃CH₂OH production. The results of the time-dependent ab initio nonadiabatic molecular dynamics simulation show that the diatomic N active sites of N₂@BP_V facilitate charge separation and inhibit electron-hole recombination. In addition, the activation mechanism of CO₂ is studied. The main reason for CO₂ activation is attributed to the imbalance in electron transfer that destroys the symmetry of CO₂. We expect that our study will offer some theoretical guidance in CO₂ conversion.