Abstract This study proposes a novel method to maximize efficiency at various frequencies and duty cycles in hydrogen production through water electrolysis. To analyze the frequency response, we model the water electrolysis as electrical components and assume all electrical components operate within their linear region. To maintain operation in linear region we consider the pulse width which is necessary for electrolysis without formation of the diffusion layer. We modeled the water electrolysis using an innovative electrical circuit to facilitate analysis in the frequency domain. Our assumptions involved typical values for double layer capacitance (C dl ) and charge transfer resistance (R ct ) in alkaline electrolysis, particularly in KOH-based systems, which range from 1 to 100 µF/cm² and 0.5 to 20 ohms, respectively. across a frequency spectrum of 0 to 50 kHz. Moreover, we examined the influence of duty cycle on the electrolyzer’s performance by applying Fourier series coefficients. Our investigation of duty cycles at 5%, 10% and 15% revealed that the efficiency is maximized at a 5% duty cycle compared to higher duty cycles. Ultimately, our results demonstrate that achieving optimal efficiency necessitates a careful balance between operating frequency and duty cycle, which is crucial for preventing diffusion layer formation and improving overall system performance.

Pulsed dynamic electrolysis (PDE), driven by renewable energy, has emerged as an innovative electrocatalytic conversion method, demonstrating significant potential in addressing global energy challenges and promoting sustainable development. Despite significant progress in various electrochemical systems, the regulatory mechanisms of PDE in energy and mass transfer and the lifespan extension of electrolysis systems, particularly in water electrolysis (WE) for hydrogen production, remain insufficiently explored. Therefore, there is an urgent need for a deeper understanding of the unique contributions of PDE in mass transfer enhancement, microenvironment regulation, and hydrogen production optimization, aiming to achieve low-energy consumption, high catalytic activity, and long-term stability in the generation of target products. Here, this review critically examines the microenvironmental effects of PDE on energy and mass transfer, the electrode degradation mechanisms in the lifespan extension of electrolysis systems, and the key factors in enhancing WE for hydrogen production, providing a comprehensive summary of current research progress. The review focuses on the complex regulatory mechanisms of frequency, duty cycle, amplitude, and other factors in hydrogen evolution reaction (HER) performance within PDE strategies, revealing the interrelationships among them. Finally, the potential future directions and challenges for transitioning from laboratory studies to industrial applications are proposed.

Green hydrogen as an environmentally-friendly power source Hydrogen is the most plentiful chemical element in the visible universe. The mass composition of the visible universe is approximately 74% hydrogen, 24% helium, 1% oxygen, and the rest of all other chemical elements is about 1%. Hydrogen has the symbol H and the atomic number 1. It is placed in the first position in Mendeleev's periodic table of elements, in the upper left corner. It is an easily flammable, colorless, tasteless, odorless gas, and in nature, it is found mainly in the form of the diatomic molecule, H 2. With an atomic mass unit of 1.00794, hydrogen is the lightest chemical element. Etymologically, the word hydrogen is a combination of two Greek words hydor and gennan meaning: water producer. Hydrogen (H 2) has a very good calorific value per mass unit 143 MJ/kg which is 3.33 times more than the calorific value of kerosene or diesel fuel. Green hydrogen (clean hydrogen or renewable hydrogen) is produced by electrolysis of water (splitting of water into hydrogen and oxygen) using electricity from renewable sources such as solar energy, wind energy, seawater waves energy, or tidal power.

One example of a decomposition reaction is the electrolysis of water to make oxygen and hydrogen gas: 2 H 2 O ⟶ 2 H 2 + O 2 {\displaystyle {\ce {2H2O->2H2 A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an energy change as new products are generated. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bond One example of a… I…

Electrolysis Electrolysis is a scientific way of 'splitting' substances. It means 'electric-splitting' and involves the separation of substances through an electric current. Metals above carbon in the reactivity series (potassium, sodium, lithium, calcium, magnesium and aluminium) are extracted by electrolysis. Uses Electrolysis is used in the mining industry to split reactive metals from their ores after they are taken from the ground. Electroplating is also a process that uses electrolysis. It is used to plate (cover) things with metal, because it costs less than using materials like solid gold to make jewellery. Electrolysis can be used by a trained doctor or esthetician to remove hair. This is called electrology. The "galvanic" method of electrology uses electrolysis to produce a very small amount of a caustic solution, containing sodium hydroxide and water, by running an electrical current through a metal probe inside of the hair follicle. The method uses the body's tissues as an electrolytic cell, since these contain water and salts (electrolytes). The caustic solution reacts with the cells inside of the follicle, and damages them so that they cannot grow a hair anymore.