High-Selectivity Electrocatalytic Ammonia Oxidation on Mo Single-Atom Catalysts Supported on BP@ZrC

Abstract

The efficiency of electrochemical ammonia oxidation is severely limited by its selectivity, and current designs of electrochemical ammonia oxidation reaction catalysts lack targeted research on the structure-activity relationship. In this work, transition metal single-atom catalysts were constructed based on BP@ZrC substrates, and the thermodynamic stability and catalytic activity for the catalyst were systematically investigated through the density functional theory calculations. The first-principles calculations demonstrated that the designed catalyst structure could effectively inhibit the nitrogen-oxygen coupling side reaction. According to the volcano plot, Mo-BP@ZrC was selected as the optimal catalyst, with a low theoretical overpotential of 0.49 V and 100% selectivity for N2. By comparing the catalysts with different substrates and doping atoms, the activation mechanism of the key intermediate NH2* was analyzed. The revealed the regularity on the density of states and the clear structure-activity relationship were found for the design electrochemical ammonia oxidation reaction catalysts. This work provides high-performance candidate catalysts for electrochemical ammonia oxidation reaction and also offers a theoretical foundations for developing efficient electrochemical reaction catalysts.