Synthesis of Zn(InxGa1-x)2O4 solid-solutions with tunable band-gaps for enhanced photocatalytic hydrogen evolution under solar-light irradiation

The systematic investigation of In 3+ ions doped ZnGa 2 O 4 applying to photocatalytic H 2 evolution (PHE) under simulated solar-light irradiation was first reported here. A series of Zn(In x Ga 1- x ) 2 O 4 ( x  = 0 to 0.4) solid-solutions were obtained by sol-gel method and characterized by XRD , SEM, elemental mapping, XPS , UV–Vis DRS and N 2 adsorption measures. The concentration of In 3+ ions remarkably enhanced the light-harvesting capability of Zn(In x Ga 1- x ) 2 O 4 solid-solutions in the visible-light region, and successfully regulated the positions of the CB-bottom potential, ultimately improving the photocatalytic capabilities under simulated solar-light irradiation. Among composites containing different In 3+ ions dosages, Zn(In 0.1 Ga 0.9 ) 2 O 4 demonstrated the most excellent photocatalytic capability for solar-light-driven PHE reaction (H 2 : 240.6  μ mol/h/g), in which the stability of the Zn(In 0.1 Ga 0.9 ) 2 O 4 was confirmed by several techniques.