# What are the factors that affect the redox reactions?

In my work, I used $\ce{Co(OH)2}$ and $\ce{Ni(OH)2}$ as an active materials to fabricate as symmetric supercapacitors in which I used 1-butyl-1-methylpyrrolidinium dicyanamide as an electrolyte.

From my CVs curve, I found that $\ce{Co(OH)2}$ have a high redox peaks while for $\ce{Ni(OH)2}$, it shows no redox reaction peaks. What might be the factor that affects this? As I've known both active materials have similar layered liked-structure. Is it the electronegativity differences between an electrolyte and the materials?

What could possibly affect the redox reactions and how could I study more on the reaction mechanism?

• I don't know much about it, but I believe the simplest theory, and apparently a very good one, for describing these kinds of processes is Marcus Theory – jheindel Dec 14 '17 at 0:06
• I assume that you are using cyclic voltammetry, if this is the case then electrode preparation and/ or surface properties are usually important. If the reaction is not reversible, due to side reactions/decomposition then very odd traces can be obtained. – porphyrin Jan 11 '18 at 18:13
• @Jheindel You are correct in noting that Marcus Theory is the one to use. It has been confirmed, mainly by photo-induced reactions, where the two reacting species are fixed in space relative to one another. see Harrison, et al., Chem. Phys. 116, 429 (1987), & Reid et al. J. Am. Chem. Soc., 2002, 124 (19), pp 5518–5527. – porphyrin Jan 11 '18 at 18:18