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Seawater contains hydrogen, oxygen, sodium, and other elements that are essential for life on Earth. However, such complex chemical compositions also make it difficult to extract hydrogen from them for use in clean energy. According to foreign media reports, researchers from the U.S. Department of Energy’s SLAC National Accelerator Laboratory and Stanford University, in collaboration with the University of Oregon and Manchester Metropolitan University, have developed a method to extract hydrogen from the ocean by using a dual-mode system to collect seawater for power generation. It has been proven that this innovative design successfully produces hydrogen without generating large amounts of harmful by-products. This research finding may help promote the production of low-carbon fuels. Hydrogen is a low-carbon fuel that is currently used in various applications; for example, it is used to power fuel cell vehicles and as a fuel for long-term energy storage, enabling the storage of energy in power grids for weeks, months, or even longer. Researchers say that many people try to produce hydrogen using fresh water or desalinated water, but such methods are both expensive and energy-intensive. Treated water is easier to handle because it contains fewer substances (chemical elements or molecules) floating around. However, purified water is very expensive, requires energy, and increases the complexity of the equipment. Another option is to use natural fresh water. In addition to being a finite resource on Earth, fresh water contains certain impurities, which also pose a problem for modern hydrogen extraction technologies. To treat seawater, the research team used a bipolar (double-layer) membrane system and tested it using electrolysis (a method that uses electricity to drive ions or charged particles to carry out desired reactions). The researchers began their design by controlling chloride, the most harmful element in the seawater system. The bipolar membrane system used in the experiment can create the conditions necessary for hydrogen production and reduce the risk of chloride ions entering the reaction zone. An ideal membrane system primarily has three functions: separating hydrogen and oxygen from seawater ； Helps move useful hydrogen ions and oxygen ions, while restricting other seawater ions ； Helps prevent unnecessary reactions. It is very difficult to combine these three functions, and the research team’s goal is to explore systems that can effectively integrate these three requirements. Specifically, in the experiment, protons, namely positive hydrogen ions, pass through one of the membranes and reach a location where they are collected and converted into hydrogen gas through interaction with a negatively charged electrode (cathode). The second membrane in the system allows only negative ions such as chlorides to pass through. Daniela Marin, a graduate student at Stanford University’s School of Chemical Engineering, said that as an additional safeguard, a layer of membrane contains negatively charged groups attached to it, which makes it more difficult for other negatively charged ions such as chloride ions to move to places where they shouldn’t go. In the experiments conducted by the research team, it was shown that this negatively charged film can effectively block almost all chloride ions, and the operation of this system does not produce any toxic by-products such as bleach or chlorine. The researchers say that in addition to designing the seawater-hydrogen membrane system, this study also provides a better understanding of how seawater ions pass through the membrane. This knowledge can help scientists design stronger membranes for other uses, such as in oxygen production. Next, the team plans to improve the motors and membranes by using richer and more easily extractable materials. The team stated that improvements to this design can make it easier to apply electrolysis systems in energy-intensive industries such as the transportation sector for hydrogen production.