Controlled synthesis of GaN-based nanowires for photoelectrochemical water splitting applications

Photoelectrochemical (PEC) water splitting using semiconductor materials as light absorbers have been extensively studied. Several semiconducting materials have been proposed, such as TiO₂, ZnO, and GaN. Because the efficiency of PEC water splitting is dependent on visible light absorption, the ability to tune the bandgap of GaN by alloying with In makes it advantageous over other wide bandgap semiconductors. The fabrication of GaN-based materials with nanoscale geometry offers more merit for their use in PEC water splitting. In this review, we provide an overview of the recent progress made in the synthesis and application of GaN-based nanomaterials in PEC water splitting. The outstanding challenges and the future prospects of this field will also be addressed.