Investigation of SnO2 thin film evolution by thermoanalytical and spectroscopic methods

The thermal evolution process of a SnO2 thin film from SnCl2·2H2O precursor dissolved in ethanol was followed by thermogravimetry combined with mass spectrometry (TG-MS), diffuse reflectance Fourier transform infrared spectroscopy (DRIFT) and infrared emission spectrometry (IRES). The precursor salt solution was deposited on a titanium metal sheet. After evaporation of the solvent, the gel-like film was heated in a thermobalance in an oxidative environment to 600 °C. Mass spectrometric ion intensity curves showed the liberation of chlorinated species, alcoholic fragments and CO2 as combustion product and from the decomposition of surface carbonyls, carboxylates and carbonates. The presence of OH, CH and CO bands in the infrared spectra was confirmed and their assignment was made by the deconvolution of the recorded curves as a function of the firing temperature.