Transition-metal-atom-pairs deposited on g-CN monolayer for nitrogen reduction reaction: Density functional theory calculations

The development of highly active DFT catalysts for an electrocatalytic N-2 reduction reaction (NRR) under mild conditions is a difficult challenge. In this study, a series of atom-pair catalysts (APCs) for an NRR were fabricated using transition-metal (TM) atoms (TM = Sc-Zn) doped into g-CN monolayers. The electrochemical mechanism of APCs for an NRR has been reported by well-defined density functional theory calculations. The calculated limiting potentials were -0.47 and -0.78 V for the Fe-2@CN and Co-2@CN catalysts, respectively. Owing to its high suppression of hydrogen evolution reactions, Co-2@CN is a superior electrocatalytic material for a N-2 fixation. Stable Fe-2@CN may be a strongly attractive material for an NRR with a relatively low overpotential after an improvement in the selectivity. The two-way charge transfer affirmed the donation-acceptance procedure between N-2 and Fe-2@CN or Co-2@CN, which play a crucial role in the activation of inert N=N bonds. This study provides an in-depth investigation into atom-pair catalysts and will open up new avenues for highly efficient g-CN-based nanostructures for an NRR. (C) 2021, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

This study explores the use of atom-pair catalysts (APCs) for N-2 reduction reaction (NRR) and identifies Fe-2@CN and Co-2@CN as superior catalysts with high suppression of hydrogen evolution reactions. Further research may lead to the development of highly efficient g-CN-based nanostructures for NRR.