H2S-sensing characteristics of Cd2Sb2O7 thick film sensor prepared by co-precipitation method

Sensing properties to dilute volatile sulfides such as H2S, CH3SH and (CH3)2S have been investigated for Cd2Sb2O7 thick film sensor prepared by precipitation method. Cd(NO3)2·4H2O and Sb2O3 were used as staring materials. Effects of calcining temperature on gas-sensing properties, sensitivity-operating temperature, and sensitivity-gas concentration were investigated. The crystal structure and surface morphology were examined by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results demonstrated that the Cd2Sb2O7 sensor prepared by using the powder calcined at 700 °C showed high sensitivity as well as good selectivity to dilute H2S at 200 °C. Especially, the Cd2Sb2O7 sensor showed the sensitivity as high as 4 even to 0.01 ppm H2S.