Impedance Spectroscopy of Binary Mixtures of Dimethyl Silicone Fluid and Methyl Iso Butyl Ketone

A precision LCR metre was used to measure the parallel resistance (R P ) and parallel capacitance (C P ) of a capacitive cell filled with samples of binary mixes of methyl isobutyl ketone (MIBK) and dimethyl silicone fluid (DMSF), over the frequency range of 100 Hz to 2 MHz, at a temperature of 303.15 K. Using R P and C P , complex impedance Z*(ω) was computed. A four-element equivalent circuit model was used to fit the complex impedance data. The fitting provided the values of various circuit elements representing various electrical processes occurring in the capacitive measurement cell under the influence of an applied ac field. The Bode plot presentation of the complex impedance data confirmed the values of various circuit elements determined using the fitting process. Complex impedance formalism supports the observation of the electronic double-layer capacitance (EDLC) phenomena and ionic conduction relaxation phenomena.