A stable and highly efficient visible-light-driven hydrogen evolution porous CdS/WO3/TiO2 photocatalysts

It is well known that both catalytic efficiency and stability are the two important parameters of photocatalysts for visible-light-driven hydrogen production reactions. However, light-driven hydrogen evolution based applications still suffer from sluggish reaction kinetics due to the lack of high-performance photocatalysts. In this paper, we successfully synthesized a ternary porous CdS/WO3/TiO2 photocatalyst with high efficiency and stability via two-stage approach. The as-prepared samples are characterized by XRD, FESEM, EDS, TEM, XPS, and UV–Vis, respectively, which illustrated that the CdS and WO3 moieties are in-situ formed inside the porous TiO2. Particularly, the photocatalytic hydrogen (H2) evolution rate of such ternary 8% CdS/WO3/TiO2 (molar ration of CdS:WO3:TiO2 = 8:8:100) photocatalyst ranges up to 2106 μmol h−1 g−1 under visible-light irradiation, which is higher than that of pure TiO2 and other binary (CdS/TiO2 and WO3/TiO2) porous photocatalysts. The superior H2 evolution efficiency can be attributed to the coexistence of CdS and WO3 in porous TiO2 which can promote the interfacial charge transfer and separation as well as extend the light absorption up to the visible range.