CdS nanoparticles/CeO₂ nanorods composite with high-efficiency visible-light-driven photocatalytic activity

Graphical abstract: Coupling CdS with CeO₂ can effectively improve the light-harvesting ability of wide-band gap CeO₂ NRs as the photoinduced electrons on the conduction band of CdS are transfered to the conduction band of CeO₂. - Highlights: • Coupling CdS can effectively improve the light-harvesting ability of wide-band gap CeO₂. • CdS/CeO₂ composites show high photocatalytic activity under visible light irradiation. • The mechanism of photocatalytic H₂ evolution over CdS/CeO₂ was proposed. - Abstract: Different mole ratios of CdS nanoparticles (NPs)/CeO₂ nanorods (NRs) composites with effective contacts were synthesized through a two-step hydrothermal method. The crystal phase, microstructure, optical absorption properties, electrochemical properties and photocatalytic H₂ production activity of these composites were investigated. It was concluded that the photogenerated charge carriers in the CdS NPs/CeO₂ NRs composite with a proper mole ratio (1:1) exhibited the longest lifetime and highest separation efficiency, which was responsible for the highest H₂-production rate of 8.4 mmol h⁻¹ g⁻¹ under visible-light irradiation (λ > 420 nm). The superior photocatalytic H₂ evolution properties are attributed to the transfer of visible-excited electrons of CdS NPs to CeO₂ NRs, which can effectively extend the light absorption range of wide-band gap CeO₂ NRs. This work provides feasible routes to develop visible-light responsive CeO₂-based nanomaterial for efficient solar utilization.