Photoelectrocatalytic Hydrogen Generation Enabled by CdS Passivated ZnCuInSe Quantum Dot-Sensitized TiO2 Decorated with Ag Nanoparticles

Here we present the photoelectrocatalytic hydrogen generation properties of CdS passivated ZnCuInSe (ZCISe) quantum dots (QDs) supported by TiO₂ nanowires decorated with Ag nanoparticles. In this configuration, Ag nanoparticles were sandwiched between the photo-electrons collector (TiO₂) and photo-sensitizers (ZCISe), and acted as an electron relay speeding up the charge carrier transport. ZCISe and CdS enabled the optical absorption of the photoelectrode ranging from ultraviolet to near infrared region, which significantly enhanced the solar-to-chemical energy conversion efficiency. A photocurrent of 10.5 mA/cm² and a hydrogen production rate of about 52.9 μmol/h were achieved under simulated sunlight (1.5 AG).