Synergistic B/N coordination engineering in graphene-based single-atom catalysts for efficient ORR/ OER/HER: A DFT study

The rational design and development of multifunctional catalysts remain a major challenge for next-generation energy conversion and storage devices. In this study, density functional theory (DFT) calculations were employed to investigate graphene-based single-atom catalysts. Four boron (B) atoms and two nitrogen (N) atoms were incorporated into the second coordination shell of monolayer graphene, substituting carbon atoms in the lattice. A systematic evaluation of 15 transition metals (TM=Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ir, Pt) anchored at active sites was performed to assess their structural stability and catalytic activity toward the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER). The results demonstrate that modulation of the local coordination environment effectively tunes the electronic structure of transition-metal centers, thereby optimizing the adsorption behavior of key intermediates. Several promising configurations were identified that simultaneously enhance ORR, OER, and HER performance, among which Co@BN/G (0.35 V/0.47 V/0.09 V) and Rh@BN/G (0.28 V/0.25 V) exhibited particularly favorable activity and stability metrics. These findings underscore the potential of B/N coordination engineering for the development of high-performance, durable electrocatalysts. This work provides fundamental theoretical insights and practical design strategies for the advancement of multifunctional catalysts in rechargeable zinc air batteries.