The Development of FeMn2O4 Gas Sensors at Room Temperature
Different ratios of MnO2/ Fe2O3, were used after being fired to form thick film gas sensors. The films were deposited on alumina substrates. The response of the sensors for a concentration range of 2500-5000 ppm increasing by a step size of 500 ppm of propanol at room temperature was investigated. The highest response was with the 75 / 25 MnO2/ Fe2O3sensor followed by the 25 / 75 and 50 / 50 MnO2/ Fe2O3sensors. The repeatability of the 75 / 25 mol. % MnO2/ Fe2O3to propanol at two concentration ranges 500-3000 and 2500 - 5000 ppm increasing with a step size of 500 ppm at room temperature was reported. The X-Ray Diffraction (XRD) is used to determine the final composition of the materials after firing. The XRD results show that MnO2reacts with Fe2O3to form FeMn2O4with Fe2O3and Fe3O4..