BaTiO 3 sensitive film enhancement for CO 2 detection

A barium titanate thin film was deposited by drop coating for carbon dioxide detection. The measurements are based on a resistance change and provided a sensitive response to different CO2 concentrations under a humidity environment. The concentration measurement range was between 100 and 5000 ppm of CO2 in synthetic air, and likewise, the relative humidity was between 20 and 70%. The response and recovery times of the BaTiO3 based resistive sensors were determined to 2 min and 4 min, respectively, for 400 ppm of carbon dioxide and 50% relative humidity.