Preparation of tungsten trioxide film with mesoporosity by anodisation

The mesostructured WO3 film on tungsten was investigated by anodic oxidation in ethylene glycol electrolytes containing low concentrations of ionic liquids (EMim.BF4, 0.6-1.6 vol. %). The surface structure of the WO3 film as prepared can be adjusted by changing the time, potential and temperature of anodisation, and the concentration of ILs and water in the electrolyte. The sample was characterised by X-ray diffraction (XRD) and field-emission scanning electron microscope (SEM) respectively. A self-organised mesostructured WO3 can be obtained under optimised parameters. The mesostructured WO3 film is arranged in sections of arrays with an average granular diameter of 30 nm.