Thermal degradation kinetics and solid state, temperature dependent, electrical conductivity of charge-transfer complex of phenothiazine with chloranil and picric acid

摘要

Temperature dependent electrical conductivity and thermal degradation kinetics of charge-transfer (C-T) complexes of phenothiazine (PTZ) with p-chloranil (CHL) and picric acid (PA), are reported. These C-T complexes exhibited semiconducting behaviour. The activation energies for PTZ-CHL and PTZ-PA complexes are calculated based on their electrical conductivities measured over the temperature ranges 30–110°C and 30–90°C, respectively. And these energies for PTZ-CHL and PTZ-PA are 0·54 eV and 0·75 eV, respectively. The complexes are analysed for the kinetic parameters like the activation energy for decomposition and the Arrhenius pre-exponential factors in their pyrolysis region using Broido’s, Coats-Redfern as well as Horowitz-Metzger methods. Using standard equations, thermodynamic parameters such as enthalpy, entropy and free energies, are calculated.