STRUCTURAL CHARACTERIZATION AND GAS SENSING PROPERTIES OF NANO-SIZED TIN DIOXIDE MATERIAL SYNTHESIZED FROM TIN(II) SULFATE

Structural features, surface condition, and gas-sensing properties of the nanocrystalline SnO2 powders synthesized from SnSO4 precursor by different methods have been studied. XRD, TEM, BET, and FTIR methods were used for the samples characterization. The gas sensors were fabricated by the thick-film technology from the synthesized SnO2 powders. The responses of the sensors toward CO and CH4 gases are measured. It is revealed that the preoxidation of SnSO4 powder with concentrated sulfuric acid before the hydrolysis results in the lower particle size, higher surface area, improved adsorption activity, and higher sensitivity to reducing gases (CO, CH4) of the synthesized SnO2 materials, than in the case of the SnO2 materials obtained without the preoxidation stage.