Development of the Cyclic Reciprocal Derivative Chronopotentiometry with Alternating Current of Different Frequencies

Abstract

We report on the development of the cyclic reciprocal derivative chronopotentiometry (CRDC) method using the sinusoidal alternating current of different frequencies. The development consists of the transformation of the initial dependence E=f(t) to the form dq/dE=f(E) through the intermediate function dE/dt=f(E). The modificated CRDC method allows to observe the structurization of the peaks in the plot of catechol, alizarin and hematoxylin oxidation processes. The degree of structuring strongly depends on the selected frequency. This define the intermediate stage of the radical formation that is not observed in the traditional cyclic voltammetry.

Cyclic Reciprocal Derivative Chronopotentiometry as a Teaching Tool in the Electrochemistry Lab

“…Furthermore, the similitude between equations [3] and [4] brings to light a topic rarely explored in electrochemistry curses, which is the equivalency of electrochemical responses under galvanostatic and potentiostatic control. Recent works have used CDRC to make numerical simulation studies of electrode reactions coupled with Langmuir adsorption (6), and others have expanded this technique replacing the constant current pulse for a power-current time function and exponential current-time functions to study complex systems such as electrodes coated with electroactive molecular films (7), and using alternating current to observe radical formation during the oxidation of catechol, alizarin and hematoxylin, something that cannot be observed with traditional cyclic voltammetry (8).…”