Theoretical screening of transition metal atoms supported on two-dimensional Janus VSSe for HER/OER/ORR single-atom catalysts

This study constructed 96 single-atom catalyst (SAC) configurations by doping 12 transition metals onto the surfaces of two-dimensional Janus VSSe materials. Through first-principles calculations combined with VASP solvation modeling (VASPSOL), their catalytic performance for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) was systematically evaluated. The results revealed that S-Os@VSSe (Delta GH* = -0.10 eV), S-Pt@VSSe (0.07 eV), Se-Os@VSSe (-0.16 eV), and Se-Ir@VSSe (-0.06 eV) exhibited exceptional HER activity, with S-Pt and Se-Ir systems showing particular promise. For the ORR, S-Ir@VSSe (overpotential: 0.48 V) and Se-Rh@VSSe (0.32 V) demonstrated optimal performance. The most active OER catalysts were S-Pt@VSSe (0.26 V), Se-Rh@VSSe (0.44 V), and Se-Ir@VSSe (0.56 V). Notably, Se-Rh@VSSe emerged as a potential bifunctional catalyst for the ORR/OER, while S-Pt@VSSe and Se-Ir@VSSe showed dual-functional HER/OER capabilities. This work provides theoretical insights into Janus materials for SAC design.