Abstract

The electrochemical reduction of CO<inf>2</inf> (CO<inf>2</inf>RR) to valuable chemicals and fuels is a promising strategy for addressing environmental challenges. Graphitic carbon nitride (g-C<inf>3</inf>N<inf>4</inf>) is a promising electrocatalyst for CO<inf>2</inf> reduction. However, poor electron transfer and low CO<inf>2</inf> affinity often limit its catalytic performance. In this study, we employ density functional theory (DFT) calculations to systematically investigate the effect of various non-metal dopants (B, P, O, and S) on the electronic structure and CO<inf>2</inf> adsorption properties of g-C<inf>3</inf>N<inf>4</inf>. Our results demonstrated that O-C<inf>3</inf>N<inf>4</inf> preferentially catalyzes the formation of HCOOH with a low limiting potential of −0.12 V. Meanwhile, S-C<inf>3</inf>N<inf>4</inf> efficiently promotes the generation of CH<inf>2</inf>O, CH<inf>3</inf>OH, and CH<inf>4</inf> at a limiting potential of −0.58 V, as well as CO at −0.77 V. These findings provide valuable insights toward the rational design of effective non-metal-doped g-C<inf>3</inf>N<inf>4</inf> catalysts for efficient CO<inf>2</inf> conversion.