The gas-sensing properties of thick film sensors based on nano-ZnFe2O4 prepared by hydrothermal method

ZnFe2O4 sensors were fabricated from nano-ZnFe2O4 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-ZnFe2O4 powders could be obtained at a pH of 8–10 and the sensor based on the nano-ZnFe2O4 powder prepared at 220 °C exhibited the best performance, characterized by high sensitivity to low concentrations of C2H5OH at 180 °C, especially, the sensitivity to 100 ppm C2H5OH was as high as 76.