DFT Study of N‐modified Co3Mo3C Electrocatalyst with Separated Active Sites for Enhanced Ammonia Oxidation

Abstract Since the facile oxidation of ammonia is one key for its utilization as a zero‐carbon fuel in a direct ammonia fuel cell, developing the ammonia oxidation reaction (AOR) catalysts with cost‐effective and higher activity is urgently required. However, the catalytic activity of AOR is limited by the scaling relationship of the intermediate adsorption. Based on the density functional theory, the N‐modified Co 3 Mo 3 C with separated active sites of NH 3 dehydrogenation and N−N coupling has been designed and investigated, which is a promising strategy to circumvent the scaling relationship, achieving improved AOR catalytic performance with a lower theoretical overpotential of 0.59 V under fast reaction kinetics condition. The calculation results show that the hollow site (Co−Mo−Mo and Co−Co−Mo) and Co site in N‐modified Co 3 Mo 3 C play essential roles in NH 3 dehydrogenation and N−N coupling, respectively. This work not only benefits for understanding the mechanism of AOR, but also provides a fundamental guidance for rational design of AOR catalysts.