Duty Cycle Effects on the Step Potential Electrochemical Spectroscopy (SPECS) Analysis of the Aqueous Manganese Dioxide Electrode

作者：Forghani Marveh; Donne Scott W^*

来源：Journal of the Electrochemical Society, 2018, 165(3): A593-A602.

DOI：10.1149/2.0841803jes

Step potential electrochemical spectroscopy (SPECS) has previously been demonstrated as an effective method for deconvoluting charge storage processes in electrochemical capacitor materials. Herewith is described the effect of the two main experimental variables in SPECS; namely the potential step size and the electrode rest time, on the behavior of the aqueous manganese dioxide electrode. The potential step size dictates polarization at the electrode-electrolyte interface, and hence the driving force for charge storage, while the electrode rest time effects the extent to which the electrode has equilibrated before the subsequent potential step. The extent to which these experimental variables influence geometric and porous double layer formation, as well as diffusional and residual electrode processes, in the manganese dioxide electrode have been described and explained based on the current physical understanding of this electrode system. Furthermore, functional relationships were also established between the diffusional capacitance and the inverse square root of the scan rate (v(-1/2)), as well as the residual capacitance and the inverse of the scan rate (v(-1)).

• 出版日期2018