Through CV curves and GCD curves, we all can calculate the capacitance.

Four common ways:

1. Obtain EIS plot and fit the data. It is the most common method;

2. Check the H adsorption. Scan in acid solution and integral the peak (seems less helpful in your case);

3. CV in different rates. (Recommended). Scan at OCP with a potential range of 0.1 V from 20 mV/s to 100 mV/s. Fit the charge current with scan rate. The slope is capactance;

4. Current cut. Set a two-step signal. First step: stable potential (no reactions here) for several seconds. Second: set current as 0. The plot of potential will be a stable value and jump to another value, then reduce/increase gradually. The capactance can be calculated from this plot.