Fig. 6. (a) CV curves of Pn_25%C and Pt/C in an in-house built PEM electrolyzer recorded with a scan rate of 0.5 mV s⁻¹ at 80 °C (left). (b) Chronopotentiometry of Pn_25%CB at 80 °C for 100 h at an applied current density of 1 A cm⁻².