Wide-bandgap HfO2-V2O5 nanowires heterostructure for visible light-driven photocatalytic degradation

A novel HfO2/V2O5 nanocomposite has been fabricated for use as photocatalyst. HfO2 nanoparticles (NPs) were deposited on V2O5 using a precipitation method. Both commercial V2O5 particles and microwave-assisted hydrothermal (MAH)-synthesized V2O5 nanowires (NWs) were used. We demonstrate that the HfO2/V2O5 nanocomposite exhibits better photodegradation efficiency than the V2O5. The photodegradation reaction constant of the HfO2/V2O5 nanocomposite is more than 66% higher than that of the V2O5. The wide-bandgap, transparent HfO2 effectively reduces the electron-hole recombination by proving defect levels to quench the recombination. A plausible band structure is proposed to support the existence of these defect levels.