Study of ultrathin film of gold nanocomposite polyaniline for CO2 and NH3 gas sensing properties

摘要

To study the gas sensing properties for CO2 and NH3 gas, powdered gold nanocomposite polyani- line was chemically synthesized and ultrathin films were fabricated. XRD spectra of these samples indicate the polycrystalline nature of the film. UV-vis spectra showed peak at 3.8 eV corresponding to π-π* transi- tion. The relative sensitivities of the gas to air were around 70 and 530 for CO2 and NH3 gas respectively. Temperature variation of gas conductivity showed the increase of conductivity of the films up to about 42°C and then decreased for small change of temperature. Recovery time for the sample was 54 s.