Parametric Study and Electrocatalyst of Polymer Electrolyte Membrane (PEM) Electrolysis Performance.

An investigation was conducted to determine the effects of operating parameters for various electrode types on hydrogen gas production through electrolysis, as well as to evaluate the efficiency of the polymer electrolyte membrane (PEM) electrolyzer. Deionized (DI) water was fed to a single-cell PEM electrolyzer with an active area of 36 cm 2 . Parameters such as power supply (50-500 mA/cm 2 ), feed water flow rate (0.5-5 mL/min), water temperature (25-80 °C), and type of anode electrocatalyst (0.5 mg/cm 2 PtC [60%], 1.5 mg/cm 2 IrRuOx with 1.5 mg/cm 2 PtB, 3.0 mg/cm 2 IrRuOx, and 3.0 mg/cm 2 PtB) were varied. The effects of these parameter changes were then analyzed in terms of the polarization curve, hydrogen flowrate, power consumption, voltaic efficiency, and energy efficiency. The best electrolysis performance was observed at a DI water feed flowrate of 2 mL/min and a cell temperature of 70 °C, using a membrane electrode assembly that has a 3.0 mg/cm 2 IrRuOx catalyst at the anode side. This improved performance of the PEM electrolyzer is due to the reduction in activation as well as ohmic losses. Furthermore, the energy consumption was optimal when the current density was about 200 mA/cm 2 , with voltaic and energy efficiencies of 85% and 67.5%, respectively. This result indicates low electrical energy consumption, which can lower the operating cost and increase the performance of PEM electrolyzers. Therefore, the optimal operating parameters are crucial to ensure the ideal performance and durability of the PEM electrolyzer as well as lower its operating costs.