Graphyne-based single atom catalysts for oxygen reduction reaction: a constant-potential first-principles study

Abstract

Single-atom catalysts (SACs) have recently emerged as a promising electrocatalysts for the oxygen reduction reaction (ORR), demonstrating high catalytic efficiency and atomic economy. Graphyne (GY) as an exceptionally promising two-dimensional support for SACs, attracting significant research interest. Herein, electrocatalytic ORR performance of transition metal-embedded GY systems (M-GY) and their nitrogen-doped counterparts (N-doped M-GY) were investigated by using constant-potential first-principles calculations. Among them, N0-Co-GY exhibit superior ORR performance both in acidic and alkaline environment. More importantly, our study elucidates the fundamental modification mechanisms by which heteroatom doping configurations modulate the electronic structure and catalytic properties of GY-supported single-atom active sites, providing atomic-level insights into structure-activity relationships. These mechanistic insights offer guidelines for the rational engineering of atomic-scale coordination environments in SACs, particularly for optimizing intermediate adsorption energetics in oxygen electrocatalysis.