CO2 Gas Sensor based on BaTiO3 Thin Film Deposited via Ultrasonic Spray

A new approach for thin layer deposition to elaborate CO2 sensitive layers is demonstrated in this work. BaTiO3 was used as CO2 sensitive materials and SnO2 as a reference as well as to enhance the resistance of BaTiO3 film. BaTiO3 solution was elaborated by the dispersion of commercial nano-powder in ethanol. A simple sol-gel in ethanol was used to synthesize SnO2 precursor. SnO2 and BaTiO3-SnO2 thin films were deposited on SiO2 substrate by ultrasonic spray method. SnO2 shows no response to CO2 while BaTiO3-SnO2 gives response to 400 and 4000 ppm of CO2. These results are promising to continue working with this method.