Silver vanadate-coupled yttrium orthovanadate nanocomposite: An improved photocatalyst for amended visible-light-driven hydrogen evolution

The synthesis of yttrium orthovanadate (YVO4) by surfactant-aided sol-gel method is presented in this work. To enhance the visible-light activity of YVO4, 4.0-16.0 wt % of silver vanadate (AVO) nanoparticles were coupled by simple impregnation. The formed nanocomposites were applied for hydrogen (H2) production by photocatalytic reaction in a glycerol/water mixture with traces of platinum as a cocatalyst. The incorporation of 12.0 wt% AVO has boosted the H-2 evolution by > 130 times (3.000 mmol g(-1)h(-1)) to the pure YVO4 (0.023 mmol g(-1)h(-1)). These outcomes were attributed to the efficient separation of photogenerated charges as well as bandgap reduction to 2.35 eV compared to 3.54 eV in pristine YVO4. The produced H-2 could be furtherly enhanced to 3.750 mmol g(-1)h(-1) by optimizing the photocatalyst amount at 2.0 g L-1. This innovative nanocomposite could also maintain its ability to produce 96% of its original H-2 amount after the fifth regeneration cycle as well.