Dynamics of switching between the reversible states of polyaniline. The LH function approach

Dynamics of the reversible redox/conductivity state switching of polyaniline was under investigation. The high frequency (50 kHz–100 Hz) impedance/admittance of a thin film polyaniline electrode in 0.5 M trichloroacetic acid—water solution was measured. Parameters of the electrical model were analyzed as a function of the electrode potential. The LH function describing the switching between the reversible redox/conductivity states of polyaniline in terms of its magnitude, rate and potential was used to show some temperature effects on dynamics of the switching and a hysteresis observed in this process. In the temperature range 0–25 °C, the switching hysteresis is observed to decrease and the switching rate to increase with temperature. At the same time, the switching magnitude does not change with temperature in a definite way. The LH function approach can be applied to other conducting polymers. It may provide a new tool for a comparison of electrical and electrochemical properties of conducting polymers.