For type II, the peaks C2, C4 and A2 increased with the addition of water. Additionally, the current density positive of peak A1 is higher and some broad peaks become visible in this potential range. In the following potential cycles, the peaks C2 and C4 decrease, but the current densities are still higher compared to those recorded in the as-received ILs. The size of peak A2 also decreases, and its size is almost identical to that in the CV for the as-received IL after five potential cycles.