Computational identification of B substitutional doped C9N4 monolayer for electrocatalytic N2

Abstract Developing high-performance electrocatalysts with low overpotential and high selectivity for nitrogen reduction reaction (NRR) is vital to the sustainable production of ammonia (NH 3 ) at mild conditions. Recently, various B interstitial doped porous graphitic carbon nitride have been identified as efficient electrocatalysts for NRR, while the B substitutional doping has been rarely explored. In this work, three B doped C 9 N 4 monolayers have been designed (B C , B N , and B i n t ), and their efficiencies toward NRR are evaluated by performing comprehensive first-principles calculations. Our results clearly reveal that N 2 can be sufficiently activated on the B N and B i n t monolayers due to the ”acceptance-donation” interaction, and prefers to be reduced to NH 3 via the alternating mechanism. Particularly, B N monolayer shows superior catalytic activity with a rather low overpotential of 0.12 V comparing to B i n t monolayer (0.56 V). Moreover, we find that this proposed B N monolayer has not only great thermal and dynamic stabilities but also excellent suppression effect on the competitive hydrogen evolution reaction. These theoretical findings suggest that B substitutional doping strategy might be another direction for the design of high-performance B-based NRR eletrocatalysts.