A Selective Ultrahigh Responding High Temperature Ethanol Sensor Using TiO(2) Nanoparticles

In this research work, the sensitivity of TiO(2) nanoparticles towards C(2)H(5)OH, H(2) and CH(4) gases was investigated. The morphology and phase content of the particles was preserved during sensing tests by prior heat treatment of the samples at temperatures as high as 750 °C and 1000 °C. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis were employed to characterize the size, morphology and phase content of the particles. For sensor fabrication, a film of TiO(2) was printed on a Au interdigitated alumina substrate. The sensing temperature was varied from 450 °C to 650 °C with varying concentrations of target gases. Results show that the sensor has ultrahigh response towards ethanol (C(2)H(5)OH) compared to hydrogen (H(2)) and methane (CH(4)). The optimum sensing temperature was found to be 600 °C. The response and recovery times of the sensor are 3 min and 15 min, respectively, for 20 ppm C(2)H(5)OH at the optimum operating temperature of 600 °C. It is proposed that the catalytic action of TiO(2) with C(2)H(5)OH is the reason for the ultrahigh response of the sensor.