At present, most hydrogen is produced by the cracking of methane. The cracking of methane will produce a large amount of remaining carbon dioxide, and carbon dioxide is considered to be an important gas that causes global warming. For decades, scientists have been working on researching how to convert water into hydrogen and oxygen economically and efficiently through electrolysis.
For electrolyzers that separate water molecules, salt in seawater has always been a problem. High concentrations of salt will corrode the metal electrodes that initiate electrolysis current. Scientists at Stanford University have developed a new catalyst that integrates carbonate and sulfate molecules into the iron-nickel coating on the nickel anode. Carbonate and sulfate molecules have a very high negative charge. Because molecules of the same charge repel each other, they can prevent chloride ions in the salt from penetrating the coating and corroding the electrode.
The team successfully probed their prototype system using the sea water of the San Francisco Bay. During the test, even if the salt concentration was increased to three times the salt content of seawater, the coated electrolyzer could still run for more than 40 days.
Existing methods for producing hydrogen from water analysis rely on pure water, which is costly. At present, in many parts of the world, the supply of fresh water has been restricted. The production of hydrogen for fuel lithium-ion batteries by electrolyzing seawater will help deal with this problem. Although this breakthrough did not address all the challenges faced by hydrogen-powered vehicles, such as establishing a sustainable and affordable hydrogen-powered distribution network. However, if the use of renewable energy to produce hydrogen by electrolysis becomes possible, the remaining problems are expected to be resolved.