Effect of pulse potential on alkaline water electrolysis performance

In this study, the effect of pulse potential on alkaline water electrolysis energy consumption is investigated. A specially designed electrical circuit is used to observe the effect of different duty cycles and frequency values on water electrolysis energy consumption in different concentration values of alkaline solution. The results show that using pulse potential enhances the mass transport of oxygen and hydrogen bubbles due to the pumping effect. This provides less contact with oxygen bubbles to improve corrosion resistance of anode electrodes. Moreover, decreasing mass transfer losses on the electrode surface resulted in a 20-25% lower energy consumption to produce 1 mol of hydrogen in the cell. The optimum frequency for 10% and 50% duty cycle and 10% and 15% concentration are investigated. For 10% duty cycle, the optimum frequency is specified around 140-200 kHz and for 50% duty cycle, it is around 380-400 kHz for all concentration values.