Synthesis of mesoporous core-shell CdS@TiO₂ (0D and 1D) photocatalysts for solar-driven hydrogen fuel production

The hydrogen production from photocatalytic water splitting has attracted extensive attention, as a direct way to convert solar energy into a chemical fuel. Herein, we report straightforward a simple method to synthesize a mesoporous core-shell CdS@TiO₂ (0D and 1D) photocatalysts with Pt NPs as a cocatalyst for H₂ fuel evolution under solar irradiation and presence of a sacrificial agent. The thickness of the TiO₂ shell is conveniently controlled from 10 to 30 nm by simply using sol-gel chemistry. Tiny Pt NPs about 0.1, 0.5 and 1 wt.% were photodeposited on CdS@TiO₂ nanocomposite during the photoreaction of hydrogen production. The effect of core-shell nanostructures on the photocatalytic activity was investigated, including the size, shape, and BET surface area of the CdS (0D and ID), and the thickness, surface area and porosity of the TiO₂ shell. The prepared CdS@TiO₂/Pt photocatalysts absorb in the visible region of the solar spectrum and exhibit an excellent photocatalytic activity, compared with those reported in the literature. The 0D-CdS@TiO₂/Pt photocatalysts achieve H₂-evolution rate up to 4080 μmol during 6 h of sunlight irradiation. The mesoporous structure and large specific surface area of the prepared photocatalysts can accommodate more surface-active sites and facilitate the transport of charge carriers in visible light.