EFFECT OF SN/SB RATIO IN DETERMINING CRYSTALLITE SIZE OF SNO2-SB2O5 SEMICONDUCTORS

Six SnO//2-Sb//2O//5 semiconductors with different Sn/Sb ratios were prepared by the gel method. The samples, heated at different temperatures in the range 250 to 1100 degree C, were characterized by X-ray analysis, surface area determination, TG-DTA studies and SEM observations. Results indicate that the crystallite size of SnO//2 doped by antimony oxide is affected by the Sb/Sn ratio, smaller crystallites being obtained at lower antimony oxide loadings. The presence of a Sb//2O//4 phase separated from SnO//2 and the effect of antimony doping on SnO//2 are the main parameters ruling SnO//2 crystallite dimensions.