Figure 7.

Cyclic voltammograms recorded at a scan rate of 10 mV s⁻¹ in K‐phosphate of 4.1 mol kg⁻¹ 100 °C in the two‐electrode configuration. V _eq denotes equilibrium voltage for water electrolysis. The current‐voltage relationship over the NiFeO_x/Ni foam anode and NiMo/Ni foam cathode in 30 wt% KOH at 73 °C is also presented in the figure, which was adopted from our previous study. ^[73] All measurements were performed in the two‐electrode configuration using IrO_x/Ti mesh and Pt/Pt mesh as anode and cathode, respectively, under Ar bubbling. The voltage displayed in the figure has been iR‐corrected with measured impedance value. The pH level of K‐phosphate solutions was adjusted to 7.0 at 25 °C prior to the measurements.