The Swedish-German partnership has been in place since November 2025. At that time, both companies signed a term sheet for a strategic collaboration on iridium-based catalyst solutions for PEM electrolyzers. Since the price of iridium is considered one of the main reasons for the limited scaling of PEM electrolysers , the partners aim to reduce the amount of iridium required without compromising the durability of the electrodes.Subsequently, the partners launched a joint development project focused on Smoltek’s electrodes, which feature an iridium coating of 0.1 milligrams per square centimeter.
The long-term test that has now been announced builds on this collaboration and marks the next step toward industrial application. It is scheduled to begin in the fall and will last over 3,000 operating hours. The test will evaluate the operational stability of Smoltek’s nanostructured iridium catalyst layer.
For this development, the partners are combining Smoltek’s nanotechnology with Heraeus Precious Metals’ expertise in precious metal electrocatalysts and materials analysis. The goal is to reduce iridium consumption while maintaining high catalytic activity and conductivity.
Catalyst layer reduces iridium requirement to less than 0.1 milligrams
“Our nanostructured layer enables maximum charge and mass transport propertieswithin a thickness of just a few micrometers, ”said Fabian Wenger, head of research and development at Smoltek Hydrogen. “By optimizing this catalyst architecture, we simultaneously achieve high electrolysis efficiency and reduce the amount of iridium required to less than 0.1 milligrams per square centimeter.”
The German company Heraeus Precious Metals is conducting the upcoming test phase. Christian Gebauer, Head of Innovation for the Hydrogen Systems Division at Heraeus Precious Metals, said the company is looking forward to the start of the test campaign and to the material analysis necessary to validate the technology. To this end, the company is dedicating extensive resources to evaluating catalyst performance under real-world operating conditions. With its analytical and laboratory capabilities, the company is supporting all further steps toward the industrialization of low-iridium electrodes.
