Electrospray deposition of SnO2 films from precursor solution

The electrospray deposition (ESD) of SnO2 films from SnCl4.5H2O precursor solution was performed for gas sensor applications. Deposition time, solution flow rate and solution concentration were the main control parameters in the ESD process. The morphological properties of the deposited films were characterised by scanning electron microscopy. X-ray diffraction and energy dispersive X-ray analyses were employed to confirm the crystal phases and composition of the films. The best coatings with an island of particle agglomerates were observed at a flow rate of 0.12 ml min(-1), for 60 min, and at a 0.05M concentration. The crystallisation of SnO2 films was observed at 650 degrees C. The grain size and surface morphology of the films were influenced by the sol concentrations. Larger grain size and cracked surface were observed by increasing the sol concentration. The film thickness of 6 mu m and a grain size of less than 100 nm were achieved.