H2U Technologies, a next-generation electrolyzer developer, has performed durability tests on new, lower-cost, iridium-free catalyst materials that demonstrate a projected lifetime of 25,000 hr. This durability milestone represents a significant breakthrough and addresses supply chain bottlenecks for sustainable H₂ production with proton exchange membrane (PEM) electrolyzers.

Discovering non-iridium catalysts for commercial applications has been challenging, as novel materials often degrade rapidly under the harsh acidic conditions of the oxygen evolution reaction (OER). For perspective, the best iridium-free catalysts known to date offer lifetimes of approximately 1,000 hr—1,400 hr. With a baseline of over 4,000 hr of continuous operation thus far, H2U's iridium-free catalysts, tested at 10x higher current density, are demonstrating projected lifetimes of more than 25,000 hr. H2U catalysts are projected to last at least 6 yr for targeted applications, such as in PEM electrolyzers paired with curtailed renewables.

Why catalyst durability is important. As the H₂ economy grows and the demand for H₂ increases, maintaining catalyst performance without relying on iridium becomes even more critical. Durable catalysts enable the scalability of H₂ production and utilization technologies by reducing the frequency of replacements and associated costs.

The reliance on iridium has raised industry concerns, as the U.S. Department of Energy has recently categorized iridium as the sole material in the H₂ sector at high risk of supply disruptions.

H2U's innovative catalysts are cost-effective and more readily available than iridium. Utilizing these affordable alternatives expands the possibilities for electrolyzer stack design, enabling H2U to explore avenues unrestricted by ultra-thin catalyst layers and low usage of catalysts. This flexibility significantly reduces capital expenses, producing more affordable delivered H₂.

"Our talented scientists and engineers have achieved an exceptional breakthrough with rigorous testing of various families of alternative lower-cost compounds. The discovery of relatively earth-abundant materials using our Catalyst Discovery Engine™ (CDE™) has demonstrated a projected lifetime of 25,000 hr in ongoing tests, a milestone previously considered unattainable without iridium," said Mark McGough, H2U's President and CEO. "As these successful trials continue, we expect to attain further breakthroughs."

H2U's Senior Catalyst Engineer, Dr. Michael Mazza, remarked, "This achievement of a 25,000-hr lifetime is the best durability number we've seen for an iridium-free catalyst in a PEM electrolyzer. Our CDE team found promising catalysts and developed a unique process to integrate the materials into membrane electrode assemblies to optimize activity and durability. This discovery not only represents a technological leap but also contributes significantly to addressing the global need for sustainable H₂ production. We are excited about the potential impact of our team's ongoing scientific discoveries on the clean energy landscape."

H2U's discovery and testing of durable non-iridium catalysts has the potential to lower the upfront costs of electrolyzers significantly. This becomes especially important in the coming years, as the limited availability of iridium will result in shortages and significant price hikes, posing a major obstacle to a swift transition to cleaner energy.