I have a phosphate buffer adjusted to pH 7, and another phosphate buffer made of deuterium oxide (D2O) adjusted to pH 6.6 (pD 7). I want to conduct cyclic voltammetry of cobalt oxide catalyst in these buffers. I want to apply the following potential range for the buffer made of normal water: 0.9 to 1.25 V vs. NHE. So, my question is here: shall I apply the same potential range for the buffer made of D2O? or I should take the pH difference into account*?
*The pH difference would be: (7-6.6)*0.059 = 0.0236 V.
Then the potential range for buffer made of deuterium oxide would be: 0.9236 to 1.2736 V vs. NHE.