Influence of Gd+3 incorporation on ethanol sensing properties of Barium Stannate microrod films prepared by coprecipitation method

Ethanol sensing is an important area of research given its relevance to human health, traffic control and various industries. Metal oxide semiconductor nanostructures are most commonly used as gas sensors. In this study, enhanced ethanol sensing properties were obtained by incorporation of Gd3+ ions into Barium Stannate (GBSO), a bimetallic oxide microrods prepared through a simple co-precipitation method. The GBSO films, when exposed to ethanol, showed that incorporation of Gd improved the sensing response fill 3 wt% of Gd (3GBSO) loading while further increase in Gd content resulted in reduced response. 3GBSO sample showed response as high as 76 to 500 ppm of ethanol vapor at an operating temperature of 220 degrees C along with a very low detection limit of 0.1 ppm (response of 1.5). Good repeatability and moderate stability were also observed suggesting its potential as low-cost ethanol sensor. Significant increase in both specific surface area as well as oxygen content (as measured by x-ray photoelectron spectroscopy) was observed in 3GBSO sample compared to that of BSO. Thus, we showed that incorporation of Gd improved the surface area of BSO microrods and in turn the surface adsorption of oxygen which led to their enhanced response to ethanol.