Empa researchers want to produce green hydrogen more cheaply

(CONNECT) Empa researchers from the Materials for Energy Conversion laboratory are developing alternative materials for water electrolysis together with partners from the French research institutes Institut de la Corrosion in Brest and LEMTA in Nancy.

Hydrogen is considered an important component of the energy transition, as it can replace fossil fuels. When water is split into hydrogen and oxygen using electricity from renewable sources, green hydrogen is produced. When it is used, it reacts with oxygen to form water without releasing greenhouse gases. However, according to a press release, the production of green hydrogen using electrolysis is currently around twice as expensive as the production of hydrogen from fossil materials such as natural gas and is not very widespread.

The cost drivers of electrolysis are the materials used in the production of the electrolysers, the report continues. This is where the researchers come in with their Polymer Electrolyte Membrane Water Electrolysis (PEMWE) technology, which is considered efficient and is particularly suitable for fluctuating electricity production from renewable energies.

Currently, components in PEMWE electrolyzers are manufactured from corrosion-resistant titanium and later coated with the precious metal platinum. Both titanium and platinum are expensive materials that are difficult to process. The researchers therefore rely on a special form of titanium oxide, known as highly crystalline low-oxygen rutile, to replace the platinum coating for their electrolysis components. Steel is used as the carrier metal for PEMWE electrolysis.

Initial results confirm the high corrosion resistance of the alternative coating. The researchers have already successfully coated the so-called bipolar plate of a PEMWE electrolyzer with titanium oxide using physical vapor deposition (PVD). PVD is widely used in the hydrogen industry. "It is important for us to develop something that industry can actually use," Empa materials scientist Konstantin Egorov is quoted as saying.

The project will run until 2026. Once the project is completed, the researchers want to bring industrial partners on board to commercialize their electrolysis technology. ce/ja