Researchers from the University of Hong Kong have developed a breakthrough technology. A new stainless ultra-steel could solve the problem of green hydrogen production. This one material makes it possible to make durable and cheap electrolyzers for seawater.
Teacher Mingksin Huang leads the team that designed the material SS-H2. This ultra-steel is resistant to corrosion in extreme conditions. This makes it ideal for use in aggressive electrolyser environments.
A cheaper path to clean energy
Green hydrogen is produced by breaking down water using electricity from renewable sources. Seawater is an available resource, but salt and chlorine quickly destroy system components. Traditional materials, such as titanium, are too expensive for mass use.
SS-H2 material has similar performance to titanium, but is significantly more economical. It is estimated that this one steel could reduce the cost of structural parts by as much as 40 times. This is crucial for the commercial application of this technology.
Why ordinary steel fails
Classic stainless steel uses chromium to protect against corrosion. However, this protective layer breaks down at high electrical voltages. Standard steel cannot withstand the conditions required for water oxidation. Even the top seawater resistant alloys have their limitations at high voltage.
University of Hong KongRevolutionary double shield
The HKU team applied a sequential double passivation strategy. In addition to the chromium layer, at around 720 mV, another protective layer based on manganese is formed. This additional shield protects the steel up to an extremely high voltage of 1700 mV.
This discovery greatly surprised the scientific community. Manganese was previously considered an element that weakens the corrosion resistance of steel. Dr Kaiping Ju points out that this mechanism was completely unexpected according to previous knowledge.
Ultra-steel from the laboratory to industrial applications
Scientists spent six years developing this mechanism for ultra-steel. Patents have already been filed in several countries around the world. Cooperation with a factory in mainland China has already resulted in the production of the first tons of SS-H2 wire.
Although there is still engineering work to be done, the promise is quite large, but also clear. Steel that replaces expensive titanium parts can make hydrogen more available. This is a practical step towards cleaner energy on an industrial scale, concludes Science Daily.