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On the major problem of hydrogen production using electrolysis, the gas bubble is the desired product, but it also consumes more power. The pulse-activated electrolysis is a simple method that has been developed for several years. With the capability of enhancing the efficiency of an electrolytic process and easy operation, this technique becomes an interesting process for hydrogen production. Frequency is the main characteristic of the pulse activation; low frequency and high frequency are divided because of modelling concept and experimental setup. Following the assumption of natural frequency, the high frequency is used for understanding the high production rate with the parasitic inductance of the electrolyzer being considered. Unfortunately, during electrolytic reaction, the system parameters (e.g. Resistivity, Capacitive) will migrate due to the gas bubble created. At the lower frequency the model can be simplified and focused on the view of efficiency instead of productivity because the first order system has less affect to eigenvalue migration. The pulse duration time is a reciprocal of frequency, so the activation time and rest time can be considered. This paper aims to present a view of frequency on the current pulse activation. The electrical equivalent circuit was used in this research to analyze frequency response of system in order to identify and predict the electrolytic reaction. The combination of ideal gas rule and Faraday’s law of electrolysis was considered to study the activated timing parameter. In the experiment, the electrolyzer was set to 353 K, 1 atm, and used 20%wt KOH as electrolyte. The production rate and the production efficiency were observed at low frequency with various input currents and various duty-cycles. The result shows that the lower duty-cycle at the low frequency gives more advantages in efficiency enhancement.

hydrogen production, pulse-activated, optimization, duty-cycle