Capacitive properties of the hydrophobic [2-(methacryloyloxy)ethyl]-trimethyl ammonium nonafluoro-1-butanesulfonate poly(ionic liquid) thin film

The capacitive behavior of the hydrophobic fluorinated polymeric ionic liquid, poly[2-(methacryloyloxy)ethyl]-trimethyl ammoniumnonafluoro-1-butanesulfonate (poly-IL), has been investigated by current-voltage (C-V) measurements and electrochemical impedance spectroscopy (EIS) using a cell featured by a ITO/poly-IL/Al sandwich structure. The data were collected in the temperature range between 30 and 60 °C. The Nyquist plot shows a slope variation that indicates a moderate increasing of the ions mobility with temperature. The Bode diagram reveals that the sample exhibits a capacitive behavior below 104 Hz with no redox processes at the electrodes as confirmed by the C–V curves. The material shows a relatively high thermal stability, probably due to its polymeric nature making the capacitor almost insensitive to the variation of the operating temperature.