Electrochemical impedance spectroscopy (EIS) was performed at DC 0.0 V using an AC perturbation signal of 20 mV, and the frequency ranged from 100 kHz to 100 mHz. Energy (E, Wh kg -1 ) and power densities (P, W kg -1 ) of the fabricated AZIC devices were determined using the following equations: 𝐸 = 1 2 𝐶𝑉 2