A research team at the University of Hong Kong says it has created a new type of stainless steel that may help address a long-standing problem in high-potential electrochemical systems and reduce the cost of green hydrogen production.
Led by Professor Mingxin Huang of HKU’s Department of Mechanical Engineering, the group developed what it calls stainless steel for hydrogen, or SS-H2. According to the researchers, the material is designed to withstand severe corrosion in conditions that ordinary stainless steel cannot handle.
The steel is especially promising for systems that produce green hydrogen using seawater. In hydrogen production through electrolysis, electricity is used to split water into hydrogen and oxygen, and the equipment must hold up under demanding chemical and electrical conditions, especially when salt is present.
In a saltwater electrolyzer, the new steel performed at a level comparable to titanium structural parts now used in hydrogen production from desalinated seawater or acidic solutions, according to the study. The researchers say the main advantage is cost, since SS-H2 is much less expensive than titanium-based components.
The findings were published in Materials Today in a paper titled “A sequential dual-passivation strategy for designing stainless steel used above water oxidation.” The team has also applied for patents in several countries, and two have already been approved.
