Continual injection of photoinduced electrons stabilizing surface plasmon resonance of non-elemental-metal plasmonic photocatalyst CdS/WO3-x for efficient hydrogen generation

To remedy the instability problem of the non-elemental-metal (NEM) plasmonic photocatalyst WO3-x in aqueous solution, a novel strategy of photoinduced electron injection was applied to construct CdS/WO3-x hetereostructures by growing WO3-x on semiconductor CdS nanowires. Under visible/near-infrared light irradiation, the NEM plasmonic CdS/WO3-x nanowires are highly stable and exhibit a much higher activity (1.60 mmol g(-1) h(-1)) than do plasmonic WO3-x (negligible amount) and semiconductor CdS (0.53 mmol g(-1) h(-1)) in hydrogen generation. Wavelength dependent photocatalytic performance and Single-particle PL study demonstrate that photo-excited electrons on CdS continually inject into conduction band of WO3-x, so that the surface plasmon resonance (SPR) of the NEM plasmonic photocatalyst WO3-x is sustained while hot electrons generated by the SPR excitation are consumed for hydrogen generation.