Alcohols detection based on Pd-doped SnO2 sensors

In this paper a series of sensors based on SnO₂ doped by impregnation with Pd, with a ratio of 1% to 5% were prepared. These sensors have shown good sensitivity for different alcohols (ethanol, n-butanol and 1-octanol). The characterization of the doped SnO₂ was performed using N2 adsorption-desorption by the Brunauer-Emmett-Teller (SBET) surface area analysis, and Scanning Electron Microscopy (SEM). The gas sensor´s behaviour for different alcohol-vapours and different working temperature were analyzed. Although the fabrication technique does not give us a uniform and well shaped film, it was observed that the response signal of the sensor changes proportionally with the sensing temperature. The higher voltage response to ethanol was obtained with the sensor 5% Pd-SnO₂ film, and also it has been obtained good signal reproducibility when alcohols (ethanol, n-butanol and 1-octanol) were measured under the same conditions.