PN exhibits moderate charge storage capabilities with a specific capacitance of 181.3 F g -1 . It demonstrates a relatively high power density at 1058.4 W kg -1 , albeit with a moderate energy density of 31.3 Wh kg -1 . Despite this, PN maintains a high Coulombic efficiency of 130.31%. In contrast, PNZ exhibits slightly improved charge storage properties with a higher specific capacitance of 280.6 F g -1 . However, its power and energy density are comparatively lower at 774.0 W kg -1 and 25.9 Wh kg -1 , respectively. The low specific capacitance for PNZ contradicts the results from the threeelectrode measurements. The negative polarization of the respective counter electrode in the twoelectrode setup may cause losses during the GCD cycles, leading to performance loss.