Electrochemical impedance spectroscopy of mesoporous Al-stabilized TiO2 (anatase) in aprotic medium

High-frequency electrochemical impedance spectroscopy was used to investigate the mesoporous film of Al-stabilized TiO2 on F-doped SnO2 support in 1 M Li(CF3SO2)2N in ethylene carbonate/dimethoxyethane (1:1 v/v). Kinetic parameters, viz. charge transfer resistance and chemical diffusion coefficient, were determined. Charge transfer resistance increased with time of contact of electrode in the above aprotic electrolyte solution. The increase followed exponential dependence, whereas the double layer capacitance, simultaneously, decreased exponentially with time. These effects were discussed in terms of the solid–electrolyte interface, which undergoes chemical changes upon contact with the electrolyte solution.