The functional role of different carbon/semiconducting oxide hybrid nanostructures for photoelectrochemical (PEC) water splitting

This review examines the integration of carbon-based materials with semiconductor nanostructures as a promising approach for sustainable energy, through photoelectrochemical (PEC) water splitting for hydrogen production. It discusses a variety of hybrid nanostructures, such as graphene and its derivatives—carbon nanotubes, fullerenes, carbon quantum dots, carbon nanofibers, carbon spheres, and carbon nitride—combined with metal oxides, highlighting their potential to significantly enhance PEC performance. The synergistic effects between semiconductor oxides and carbon-based materials are shown to improve both catalytic activity and charge transfer, which are essential for efficient solar-to-fuel conversion. This review emphasises the importance and limitations of different carbon-based materials used alongside metal oxides. It also summarises challenges and future research directions in developing such hybrid nanostructures. These findings emphasise the potential of carbon/semiconductor hybrid nanostructures as efficient, environmentally sustainable platforms for PEC water splitting, paving the way for advancements in renewable energy technologies.