Photocatalytic water splitting for hydrogen production via heterojunction provides a convenient approach to solve the world crises of energy supply. Herein, graphene quantum dots modified TiO2 hybrids (TiO2-GQDs) with a "caterpillar"-like structure exhibit stronger light absorption in the visible region and an enhanced hydrogen production capacity of about 3.5-fold compared to the pristine TiO2 caterpillar. These results inferred that the addition of GQDs drastically promotes the interfacial electron transfer from GQDs to TiO2 through C-O-Ti bonds via the bonding between oxygen vacancy sites in TiO2 and in-plane oxygen functional groups in GQDs. Using a "caterpillar"-like structure are expected to provide a new platform for the development of highly efficient solar-driven water splitting systems based on nanocomposite photocatalyst.
Keywords: GQDs; TiO2 caterpillar; hydrogen production; photocatalysts; water-splitting.