Theoretical screening of transition metal atoms doped two-dimensional VSe2 monolayers as single-atom catalysts for HER, OER and ORR

Single-atom catalysts (SACs) have attracted considerable attention because of their excellent atomic utilization and catalytic performance. However, the choice of the carrier in SACs plays a decisive role in the catalytic performance. In this work, a series of single transition metal atoms (Fe, Co, Ni, Cu. Zn, Ru, Rh, Pd, Ag, Cd, Os, Ir, Pt, Au, Hg) doped on the two-dimensional(2D) VSe2 monolayer were selected as electrocatalysts, then we systematically calculated and investigated hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), as well as electrocatalytic oxygen reduction reaction (ORR) performance for a transition metal atom, doped VSe2 (TM@VSe2) through first-principle calculation. The results show that among all SACs, And Au@VSe2 has the lowest overpotential of 0.45 V, exhibiting excellent catalytic performance of OER. Meanwhile, Pt@VSe2 shows a good catalytic performance of HER with ΔGH* of 0.11 eV and certain catalytic performance of OER as well as ORR (ηOER = 0.72 eV, ηORR = 0.85 eV), indicating that Pt@VSe2 may be utilized as a moderate triple-functional single-atom catalyst. This work broadens the view of designing multifunctional catalysts based on 2D VSe2 materials and provides a new paradigm for the study of advanced single-atom catalysts.