Hong Kong researchers unveil ultra-corrosion-resistant steel that could slash green hydrogen costs
A team at the University of Hong Kong has created a new stainless steel, SS-H2, that resists severe corrosion and could replace pricey titanium parts in seawater-based green hydrogen electrolyzers.
Scientists from the University of Hong Kong announced a breakthrough stainless steel, designated SS-H2, that remains stable under the high voltages required for water electrolysis with seawater. Professor Mingxin Huang’s team discovered that adding a manganese-based passivation layer, which forms around 720 mV, works together with the traditional chromium oxide layer to protect the metal up to 1700 mV, far beyond the limit of conventional alloys.
Laboratory tests showed the new steel performed on par with titanium components currently used in desalinated-seawater or acidic electrolyzers, but at dramatically lower cost. The team predicts a roughly 40-fold reduction in material expenses for a 10-MW PEM electrolyzer, where structural parts can account for over half the price. Patents have been secured in several jurisdictions, and collaboration with a mainland factory has produced tons of SS-H2 wire for further scaling. If commercialized, the alloy could accelerate affordable green hydrogen production from renewable energy and seawater.
Why it matters
Cheaper, corrosion-proof steel could make large-scale green hydrogen from seawater financially viable.
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