ElectricalConductivity, Isothermal Stability, andAmmonia-Sensing Performance of Newly Synthesized and CharacterizedOrganic–Inorganic Polycarbazole–Titanium Dioxide Nanocomposite.

Electrically conductive polycarbazole–titaniumdioxide nanocomposite(PCz/TiO2) have been synthesized for the first time byin situ chemical oxidative polymerization of carbazole (Cz) in thepresence of titanium dioxide (TiO2) nanoparticles. FTIR,SEM, TEM, XRD, TGA, and DTA were used to characterize PCz/TiO2nanocomposites. The characterization results confirmed thatthere is a strong interaction between PCz and TiO2nanoparticlesand the nanocomposites showed higher thermal stability than pure PCz.The composite showed electrical conductivity and isothermal stabilityin terms of DC electrical conductivity retention under ambient conditionbelow 100 °C. A nanocomposite-based sensor was fabricated forthe detection of aqueous ammonia, it was found that the resistivityof the nanocomposites increases on exposure to ammonia at room temperature(25 °C), and it showed a linear relationship between the responsesand the concentration of ammonia. The comperative antimicrobial activitiesof PCz, its PCz/TiO2-7 nanocomposite and ciprofloxacindrug with different bacteria have also been studied. [ABSTRACT FROM AUTHOR]