Hydrogen production from gas phase photocatalytic decomposition of methanol using Pt-supported nanocrystalline WO₃ films

Nanocrystalline uniform thin films of WO₃ were fabricated by polymer assisted deposition (PAD) varying the polymer concentration in the precursor solution and the calcination temperature with controlled heating rate. The precursor solution was prepared using peroxo-tungstic acid and polyethylene glycol (PEG300) in water. The microstructure and morphology of the WO₃ thin films were studied by the XRD, AFM techniques. Nanocrystalline thin films were obtained with 20% of polyethylene glycol (PEG300) and at a calcination temperature of 350 °C. The hydrogen generation process on platinized WO₃ specimens was investigated using a six channel quadrupole mass spectrometer at a real-time scale with gaseous methanol under visible (400-700 nm), UVA (300-400 nm), and UVB (240-300 nm) light illumination. The use of WO₃ as photocatalyst opens the way for solar light powered photocatalytic hydrogen production.