Dear Shubhangi
Your question is not quite clear. My understanding that charges acquired by species normally occur because the species don't electrochemically polarized in certain aqueous solutions. This is due to the exchange current of the interface between the species and the solution is very high. In other words, the net exchange current of the interface between the species and the solution is near zero. as a result, the species would acquire charges in certain solution with a particular PH. Likewise, solid bodies acquired sometimes electrostatic charges due to friction in non-aqueous environment, in which no exchange current between the environment and the solid bodies.
The applications of cyclic voltammetry in your case is valid as a subtle instrument in a comparison to the direct voltammetry. The cyclic voltammetry would control better the polarization of those species than the direct voltammetry.
To give more specific answer, more information would be required regarding your question. And, as you know the CV is controlled variation of potential at working electrode with respect to reference electrode, for measuring the current at working electrode. By saying current, it means the exchange of electrons that might or might not cause any reaction as of if it is capacitance or reaction current.
Also, existence of species is very much related to the potential applied at the working electrode and hence there is a need to know the pourbaix diagram of that species too.
The mechanism of CV is just controlled change in applied potential and recording or observing the current as per that change.
For an equilibrium AH = A- + H+ , if only one species is electroactive (and its concentration is pH controlled) then the peak values depends on pH.
In this case H+ is involved in the overall redox equilibrium, the positions of the current peaks will also depend on pH.
Indeed, your question could have made clearer. When pH is the influencing factor on the charged state of a species, compared with non-charged species, oxidation of positively charged or protonated species would occur at more positive potential, and reduction of it at less positive potential. For negatively charged or deprotonated species, the opposite applies.
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