High-purity WO 3 sol–gel coatings: synthesis and characterization

WO3 thin films obtained by the sol–gel technique from ethanolic solutions of W2[OC(CH3)3]6 were deposited on pure silica and heat treated at different temperatures. Their chemical and structural characterization was obtained by X-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectrometry (RBS), scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–VIS spectroscopy and atomic force microscopy (AFM). The microstructure, morphology and the residual carbon content of the coatings were found to be highly dependent on the temperature of the heat treatment.