Theoretical study of Au–NX–C catalysts for H2O2 electrosynthesis via two-electron oxygen reduction reaction

Abstract

Single-atom catalysts demonstrate remarkable activity and selectivity in H₂O₂ electrosynthesis via two-electron oxygen reduction reaction (ORR). Currently, the predominant strategy employed to enhance the selectivity for H₂O₂ production and subsequently improve the overall H₂O₂ yield involves dispersing metal sites exhibiting high activity. However, a noteworthy research gap exists in enhancing catalytic activity and H₂O₂ yield by modifying low-activity dispersed metal sites. In this study, we introduce Au–N₄–C as a highly promising catalyst for the electrochemical production of H₂O₂. Using density functional theory and first-principles analysis, we analyze the active centers, conductivity, catalytic activity, and selectivity of Au–N_X–C catalysts with distinct N-vacancy structures. The findings demonstrate that the Au–N₄–C structure exhibits desirable conductivity and robust Au–O bonding upon O₂ adsorption, resulting in superior 2e⁻ ORR catalytic activity and favorable 2e⁻ ORR selectivity. These results validate the effectiveness of the proposed method in enhancing the catalytic performance of single-atom catalysts, thereby enabling more efficient production of H₂O₂ through adjustment of the coordination environment of the metal active center. Furthermore, these results offer valuable insights into the exploration of single-atom catalysts for the electrochemical production of H₂O₂.