SYNTHESIS, CHARACTERIZATION AND GAS SENSING PERFORMANCE OF SOL-GEL PREPARED NANOCRYSTALLINE SnO₂ THIN FILMS

Nanocrystalline SnO2 thin films were successfully prepared using sol-gel dip coating technique. The starting precursor was used as tin chloride dihydrate (SnCl2.2H2O), ethanol and glycerin. As the prepared films were fired at 500oC. These films were characterized using XRD, FESEM and TEM to known crystal structure, surface morphology and microstructure property. Elemental composition was studied using energy dispersive spectrophotometer (EDAX). The H2 gas sensing performance of nanocrystalline SnO2 thin films were investigated and presented. It was found that the nanocrystalline SnO2 thin films gives maximum gas response (S= 360) at 75 oC. The sensor shows fast speed of response (TResponse = 2 s) and quick recover (Trecover = 8 s).