Influence of designed electrode surfaces on double layer capacitance in aqueous electrolyte: Insights from standard models

Highlights: • Simple analytical models have been developed for three different electrode surfaces for electrical double layers. • The models did not involve assumptions and rigorous treatment. • Double layer potential and areal capacitance of EDL were stimulated for three different surfaces. • The charge/discharge profiles as well as impedance were accounted for three different pores surface area. • The cylindrical-type surface exhibited large areal capacitance. Standard models, Helmholtz, Gouy-Chapman, Stern and Grahame models have been validated on the electrical double layers (EDLs) formed from three different electrode surfaces, i.e., plain, semi-sphere and cylindrical pore in aqueous electrolyte. The double layer potential (ϕ) and areal capacitance (C_dl) were estimated in the three models using MATLAB Simulink. It was found that the areal capacitance of the double layer strongly influenced by the nature/ type of the electrode surface in contact with the electrolyte. The cylindrical-type pore surface exhibited the large areal capacitance. The charge-discharge and impedance characteristics of the EDLs were also analyzed.