Surface modified BaTiO3 thick film resistors as H2S gas sensors

The thick films of BaTiO3 were prepared by screen-printing technique. The dipping technique was used to obtain surface chrominated BaTiO3 films. The sensitivity, selectivity and the stability of pure and chrominated BaTiO3 films were measured in the presence of air and H2S gas (100 ppm). The role played by the chromium species to enhance the sensitivity and to improve the selectivity and stability of the sensor is discussed. The reasons behind the fast response and recovery of the sensor are also discussed.