The electrochemical impedance measurements indicate a decrease in double layer capacitance value and increase in charge transfer resistance for the nitrided specimens compared to the untreated ones.
Despite a decrease in double layer capacitance value of about 10%, the total capacitance of the AQ-modified on-chip CDC electrodes was twice larger than that of pristine CDC film, leading to high total capacitance value of 44 mF.cm−2 (338 F.cm−3).
The systematic trends of the influence of surface roughness and energetic inhomogeneity on the electric double layer characteristics (value of differential capacity, potential of diffuse minimum, Parsons-Zobel factor, inner layer capacity, roughness function) have been established.
The single electrode double layer capacitance value measured for the deposit is 338 mF cm−2, which translates into a specific capacitance of 50 F g−1 without any post-thermal treatment of the electrode, suggesting its utility in super capacitors.
Analysis of impedance data has been made with equivalent circuit with constant phase angle element for calculation of double layer capacitance values.
In the hydrogen adsorption region, the double layer capacity values were 14 ± 5 μF/cm2, in good agreement with previous estimates reported in the literature by using other approaches.
The presence of the solvent molecules reduces the thickness of the electric double layer, lowers the value of the mean electrostatic potential and raises capacitance.
Higher charge transfer resistance (Rct) and lower double layer capacitance (Qdl) values were obtained for pulsed deposited coatings.
Increasing the CeO2-content of the materials causes an increase in their active surface area, as supported by the anodic voltammetric charge, qa, and double layer capacitance, Cdl, values.
High charge transfer resistance (Rct) and low double layer capacitance (Cdl) values from EIS suggest that the PoPD film exhibits excellent corrosion inhibition behavior on MS in acid environment.
