Photo-assisted high performance single atom electrocatalysis of the N2 reduction reaction by a Mo-embedded covalent organic framework

Abstract

The development of highly efficient, low cost and environment-friendly solutions for the conversion of nitrogen gas to ammonia under ambient conditions has great industrial and academic significance. Single-atom catalysis (SAC) is recognized to have high potential in this area due to its rich chemical and physical properties. In this work, we proposed a Mo atom anchored covalent organic framework (MoPc-TFPN) for photo-assisted electrocatalysis of the N₂ reduction reaction using first-principles calculations. Our theoretical results demonstrated that this MoPc-TFPN catalyst has a considerably low onset potential of −0.24 V, which is comparable to or better than those of widely used noble catalysts. Because Mo denotes electrons to the Pc-TFPN substrate, the positive charged Mo has low binding affinity to H, thus greatly suppressing the competing hydrogen evolution reaction (HER). More importantly, the MoPc-TFPN has appropriate band edges with high light-absorption efficiency, which could be beneficial to improve the electrocatalytic efficiency of the NRR. This work uncovers a promising strategy for nitrogen fixation by photo-enhanced electrocatalysis under ambient conditions which could combine the ultimate functions of 2D semiconducting nanostructures for high performance catalysis.