The spin-orbit coupling induced spin flip and its role in the enhancement of the photocatalytic hydrogen evolution over iodinated graphene oxide

The conductivity, carrier concentration, and mobility of iodinated graphene oxide (I-GO) are significantly increased about five orders of magnitude compared with pristine graphene oxide (GO). The exceptional electrical properties of I-GO are mainly attribute to I3− and I5− implanted into the surface of GO, which lead to a larger Rashba spin-orbit coupling induced by heavy adatoms with active electrons living in p orbitals. The spin direction of I-GO via flipping up is confirmed. The tunneling of an electron between two carbon atoms through the polyiodides p orbitals opens additional channels for hopping in I-GO, which give rise to the superior charge transfer performance. With the help of these properties, a highly active H2 evolution has been achieved over I-GO/Pt catalyst under visible light irradiation. Thereinto, I-GO not only provides a large area and two-dimensional substrate for the confined growth of uniformly sized Pt quantum dots but also greatly enhances the transfer of photoelectrons from excited EY to the Pt co-catalyst because of its promotion of charge separation, leading to the significant enhancement of photocatalytic hydrogen evolution.