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

Abstract

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.