Study the Structural and Optical Properties of Cr doped SnO2 Nanoparticles Synthesized by Sol-Gel Method

Abstract

Chromium doped tin oxide Sn1-xCrxO2 (where x=0, 0.05, 0.10 and 0.15) nanoparticles were prepared by sol-gel technique. The nanoparticles were prepared by adding only distilled water to the raw materials which was SnCl4 .5H2O as a precursor and Cr (NO3)3.9H2O for doping. XRD patterns show that the obtained nanopowders is SnO2 with tetragonal phase fully compatible with (JCPDS) card no. 41-1445.The crystallite size was calculated by Scherrer and Williamson-Hall formula and was found to be 14.8-19.6nm and 13-18.4 nm respectively. The prepared nanopowders were examined by SEM, which revealed that they have a spherical or semi-spherical shape with some agglomeration and EDX confirm presence of Sn, Cr and O2 elements. FTIR examination revealed that the changing in the shapes and positions of absorption peaks indicates to presence of stretching modes, which are give an indication of successful doping Cr to tin dioxide nanoparticles. The wavelength range (350-1100) nm was used to study the optical properties. The measurement showed that the nature of the optical transitions represented direct allowed with energy gap varies in the range of (3.6-2.3) eV with change of Cr ratios parameter. The UV absorption, transmittance, reflection spectrum and optical constant computed of the prepared samples.