A renewable photocatalytic system with dramatic photocatalytic activity for H2 evolution and constant light energy utilization: eosin Y sensitized ZnWO4 nanoplates loaded with CuO nanoparticles

Abstract

It is necessary for the commercialization of sunlight-driven H₂ evolution to develop an efficient photocatalytic system whose energy utilization is independent of incident light intensity. Unfortunately, limited attention has been paid to the effect of light intensity on energy utilization. For all the above reasons, a photocatalytic system made up of eosin Y, ZnWO₄ nanoplates and CuO nanoparticles was fabricated. Meanwhile, its photocatalytic activity for H₂ evolution was evaluated under illumination with various light intensities. In light of the experimental results, we can conclude that the aforementioned system possesses dramatic photocatalytic performance for H₂ evolution. Under strong illumination (100 mW cm⁻²), the highest H₂ evolution rate is as high as 4.9 mmol g⁻¹ h⁻¹. Even if under weak illumination (10 mW cm⁻²), the H₂ evolution rate is still 0.53 mmol g⁻¹ h⁻¹. More interesting, the energy utilization of this system is independent of light intensity. These results might provide some new ideas for the design and preparation of high-efficiency photocatalysts with light intensity-independent energy utilization.