Synthesis of Nanostructured Tin Oxide (SnO2) Powders and Thin Films Prepared by Sol-Gel Method

Abstract

Nanocrystalline SnO2 powder was successfully prepared by using simple sol-gel technique. The sol-gel obtained was washed and calcinated at 400 C to obtain the SnO2 nano-powder. The structural property of (SnO2) nanocrystalline powder was investigated by using X-ray diffraction (XRD) technique. The optical properties were studied using Uv-Vis Spectroscopy, by recording the absorbance and transmittance spectra. The XRD pattern of the as-prepared sample demonstrated the formation of a rutile structure of SnO2 nanocrystallites. The Scanning Electron Microscopic (SEM) analysis showed a homogeneous distribution of quite small grains over scanned area. The Uv-Vis absorbance spectra also showed a characteristic peak of absorbance at   312 nm corresponding to SnO2. The energy band gap measurement for nanocrystalline SnO2 thin film was done from the graph of variation of (hν)2 versus hν. The measured value of optical bandgap energies for SnO2 thin film is 3.78 eV. The results show that the transmittance of the synthesized SnO2 film is 78 % in the spectral range 350 nm to 800 nm.