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

Abstract

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 H2 evolution by > 130 times (3.000 mmol g−1h−1) to the pure YVO4 (0.023 mmol g−1h−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 H2 could be furtherly enhanced to 3.750 mmol g−1h−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 H2 amount after the fifth regeneration cycle as well.