Enhanced d- overlap in a graphene supported Ni/PtNi heterojunction for efficient seawater hydrogen evolution

d-pi overlap, which represents overlap between metal-d and graphene-pi orbitals to facilitate electron transfer, has rarely been reported. Ni/PtNi-G2 exhibits exceptional performance in seawater hydrogen evolution due to the electron-rich surface on Pt resulting from enhanced d-pi overlap and subsequent electron transfer from graphene and Ni to Pt. d-pi overlap, which represents overlap between metal-d and graphene-pi orbitals to facilitate electron transfer, has rarely been reported.