The gas-sensing properties of thick film sensors based on nano-ZnFe_2O_4 prepared by hydrothermal method

摘要

ZnFe_2O_4 sensors were fabricated from nano-ZnFe_2O_4 powders prepared by hydrothermal method and their gas-sensing properties were investigated. It was found that the phase composition of the product and the gas-sensing properties greatly depend on the reaction pH value and the reaction temperature. Nano-ZnFe_2O_4 powders could be obtained at a pH of 8-10 and the sensor based on the nano-ZnFe_2O_4 powder prepared at 220℃ exhibited the best performance, characterized by high sensitivity to low concentrations of C_2H_5OH at 180℃, especially, the sensitivity to 100 ppm C_2H_5OH was as high as 76.