According to the power law i=av^b, for a material (reduced graphene oxide) to be capacitive the value of b=1 whereas b=0.5 for battery like behaviour.
However, the CV shows a quasi rectangular behaviour which means EDLC behaviour. On the other hand I am getting b=0.527 which shows battery behaviour. What to do ?
Samhita Pappu the material is reduced graphene oxide. But there is lot of contradictions in the result, one time i am getting the value of b=0.9 on the other hand I am also getting b=0.5 which means that sometimes material is behaving as capacitive and sometimes material is behaving as battery. How to conclude which one is true, since i am using the material to study the capacitive property
Dear Garima Chaturvedi
Your sample has a lot of functional groups that contributed to the Faradic reactions (pseudocapacitive (questionable) or simply energy storage behavior). So, depending on the potentials materials show capacitive and pseudocapacitive behavior. Try analysis at 0.85 V, b should be near 1.
Also, dear Garima Chaturvedi ,
you 'must do', at least, some GCD[1] (Galvanostatic Charge-Discharges) experiments, using a wide range of (different, parametric) current densities.
1. See Fig.4(d) in: Three dimensional NiS2–Ni(OH)2/CNT nanostructured assembly for supercapacitor and oxygen evolution reaction https://www.sciencedirect.com/science/article/pii/S0925838819333729
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