Alqahtani, MahdiKafizas, AndreasSathasivam, SanjayanEbaid, MohamedCui, FanAlyamani, AhmedJeong, Hyeon-HoChun Lee, TungFischer, PeerParkin, IvanGraetzel, MichaelWu, Jiang2020-10-292020-10-292020-10-292020-10-1410.1002/cssc.202002004https://infoscience.epfl.ch/handle/20.500.14299/172880WOS:000577608800001Photoelectrochemical (PEC) water splitting is a promising clean route to hydrogen fuel. The best-performing materials (III/V semiconductors) require surface passivation, as they are liable to corrosion, and a surface co-catalyst to facilitate water splitting. At present, optimal design combining photoelectrodes with oxygen evolution catalysts remains a significant materials challenge. Here, we demonstrate that nickel-coated amorphous three-dimensional (3D) TiO(2)core-shell nanorods on a TiO(2)thin film function as an efficient hole-extraction layer and serve as a protection layer for the GaAs photoanode. Transient-absorption spectroscopy (TAS) demonstrated the role of nickel-coated (3D) TiO(2)core-shell nanorods in prolonging photogenerated charge lifetimes in GaAs, resulting in a higher catalytic activity. This strategy may open the potential of utilizing this low-cost (3D) nanostructured catalyst for decorating narrow-band-gap semiconductor photoanodes for PEC water splitting devices.Chemistry, MultidisciplinaryGreen & Sustainable Science & TechnologyChemistryScience & Technology - Other Topicsgaasnanorodsphotoanodestransient-absorption spectroscopywater splittingtransient absorption-spectroscopyp-n heterojunctionwater oxidationphotogenerated holeshematite photoanodescharge-transfersolar-energysurfacegaprecombinationtext::journal::journal article::research article