An evaluation of the capacitive behavior of supercapacitors as a function of the radius of cations using simulations with a constant potential method.

We report on the atomistic molecular dynamics, applying the constant potential method to determine the structural and electrostatic interactions at the electrode-electrolyte interface of electrochemical supercapacitors as a function of the cation radius (Cs, Rb, K, Na, Li). We find that the electrical double layer is susceptible to the size, hydration layer volume, and cations' mobility and analyzed them. Besides, the transient potential shows an increase in magnitude and length as a function of the monocation size, , Cs > Rb > K > Na > Li.