AgInS2-sensitized CdO nanorod array photoanode with directional charge transport channel to achieve efficient photoelectrochemical hydrogen production

Rational band alignment that facilitates efficient separation and transport of carriers is essential for boosting the photoelectrochemical water splitting activity of photoelectrode. Herein, AgInS 2 nanoparticles (NPs) were employed to sensitize CdO nanorod arrays (NRAs) photoelectrode, establishing a directional charge transport channel for rapid carrier migration, resulting in significantly improved PEC performance. The as-constructed CdO/AgInS 2 NRAs heterojunction photoelectrode at 0 V vs. Ag/AgCl achieves a photocurrent density and a hydrogen evolution rate of 1.74 mA cm −2 and 19.45 μmol cm −2 h −1 , corresponding to 3.3-fold and 2.3-fold enhancements in comparison with the unmodified CdO NRAs photoelectrode, respectively. Electrochemical and photoluminescence (PL) measurements reveal that the directional charge transport channel established via the type-II heterojunction at the CdO/AgInS 2 interface facilitates promotes the migration and separation of charge carriers. This study demonstrates a viable approach from an interface band engineering perspective for designing efficient CdO-based photoelectrodes toward PEC water splitting for hydrogen production.