the pellet-type sno2 sensor was synthesized by the solid state method and the effects of additives such as nano zno (1-12 mol %) and nano in2o3 (1-10 mol %) on the co gas sensitivity of sensor were investigated. the optimum sintering temperature was chosen 800°c because of the porosity content of the samples. the phase analysis and microstructure of the samples were studied by x-ray diffraction...