Theoretical Explanation of Diatomic Synergies and Repulsion Interactions between ORR/OER Catalytic Intermediates.

Abstract

Oxygen reduction reactions (ORR) and oxygen evolution reactions (OER) are pivotal in energy conversion. Herein, first-principles calculations are employed to explore cooperative catalysis's influence on catalysts with doping and adsorption configurations. Specifically, doped and adsorbed metal atoms are explored on MXene, analyze bimetallic system's electronic properties via density of states, and investigate catalytic activity in homonuclear and heteronuclear diatomic cooperative reactions. It is found that heteronuclear diatomic cooperation substantially enhances catalyst activity, unveiling high-efficacy catalysts like Ni^&/Co*OOH (η^ORR/OER/Bi = 0.29/0.37/0.66 V) and Ni^&/Co*O (η^ORR/OER/Bi = 0.40/0.16/0.56 V). Such ultra-high catalytic activity is primarily attributed to the repulsive interactions between catalytic intermediates at neighboring active sites, which modulate the charge distribution at the target sites during the catalytic process, as well as the density of atomic orbital centers of the catalytic atoms. The findings offer a potential explanation for the discrepancies observed between theoretical calculations and experimental results.