Influence of VOC structures on sensing property of SmFeO3 semiconductive gas sensor

Abstract A perovskite-type SmFeO 3 oxide, which has a p -type semiconducting feature, was used as a chemo-resistive sensor material for VOC detection. SmFeO 3 particles were deposited on a comb-type Pt electrode printed on an alumina substrate. In this study, 15 kinds of VOCs (methanol, ethanol, propanol, butanol, acetic acid, propionic acid, methyl acetate, ethyl acetate, acetone, methylethylketone, benzene, toluene, xylene, ethyl benzene, and chlorobenzene) with concentrations below 10 ppm were examined in the range of 350 and 500 °C. The resistance of the sensor increased when the referenced air was contaminated with the VOCs. The sensing behavior was characterized by the relationship, R voc / R air  = 1 +  αC 1/ m . The observed results suggested the detecting ability of ppb-levels of several VOCs.