Influence of Doping on Crystallization and Resistance-Temperature Properties of Nanostructured SnO_2
(Lin Guangming Yang Hua Zhou Qifa Zhang Jinxiu(Department of Physics, Zhongshan University. Guangzhou)
The thermal stability of nano-SnO2 doped with 5% at Cu, Y and Si has beenstudied. The grain growth was found in two-step way: below the temperature of 600C, growth is slow and then is fast above that of 600℃.Doping with Y and Si can con-strain the grain growth even if in the temperature range higher than 600℃.After an-nealing at 900℃ for 2h the grain size is still smaller than 30 nm for Si doped specimen.Resistance-temperature peak can be moved to lower temperature with decreasing ofgrain size. Resistance-temperature peak appears at about 170℃ when grain size is small-er than 5 nm, whereas doping can strainghten the peak to a plateau. Si doped nano-SnO2 has higher sensitivity and dynamic response for alcohol at 200℃.