Sensitivity and stability of substituted phthalocyaninato-polysiloxane Langmuir–Blodgett films and its gas sensor

The monolayer and Langmuir–Blodgett (LB) film deposition behavior of tetrakis-4-(2,4-di-tert-amylphenoxy) phthalocyaninato-polysiloxane (R4PcPS) were studied. LB film gas-sensitive device was prepared by depositing R4PcPS LB films on a glass substrate with aluminum interdigital electrodes. The results on dynamic gas sensing response characteristics showed that the R4PcPS LB film gas-sensitive device has a higher detecting sensitivity on exposure to trace ammonia (1 ppm of NH3) in air, as well as comparatively lower detecting sensitivity to NO2 and I2 (100 ppm) in air. On the other hand, the R4PcPS LB film gas-sensitive device shows excellent stability.