Influence of polymerization temperature on NH3 response of PANI/TiO2 thin film gas sensor

Polyaniline/titanium dioxide (PANI/TiO2) nanocomposite thin films were processed on a silicon substrate with gold interdigital electrodes by an in-situ self-assembly approach for NH3 gas-sensing application, and the effect of polymerization temperature on the gas response of the PANI/TiO2 thin film gas sensor was investigated. The results showed that the PANI/TiO2 thin film prepared at 10 °C was superior to those prepared at other temperatures in terms of response properties, which also exhibited good reproducibility, selectivity and long-term stability. UV–vis absorption and surface morphology characterization of the nanocomposite thin films were performed to explain these different gas-sensing properties. The sensing mechanism was also discussed.