Toward green hydrogen production without iridium thanks to this new catalyst

The quest for green hydrogen, essential for a clean energy transition, has just reached a new milestone thanks to a major scientific breakthrough. A European team, led by the Institute of Photonic Sciences (ICFO) in Barcelona, has developed a new catalyst for water electrolysis, paving the way for industrial hydrogen production without relying on rare and costly materials like iridium.


Hydrogen is a promising energy carrier for decarbonizing our society. Unlike fossil fuels, its use as a fuel does not generate carbon dioxide. However, most hydrogen produced today comes from a process that generates significant CO2 emissions. To obtain green hydrogen, more sustainable alternatives are required.

Water electrolysis is a potential method to produce green hydrogen using renewable energies. This process relies on catalysts at the anode and cathode to speed up the decomposition of water into hydrogen and oxygen. Among electrolysis technologies, proton exchange membrane (PEM) is particularly promising due to its high energy efficiency and high production rates.

Traditionally, water electrolysis, especially PEM technology, requires catalysts based on rare elements like platinum and iridium. While these materials are effective, they present cost and availability issues, especially iridium, one of the rarest elements on Earth. Finding alternatives to these materials is therefore a major challenge.

The ICFO team has met this challenge by developing a new cobalt-based catalyst, an abundant and economical metal. Their innovative approach leverages the properties of water to stabilize the catalyst. By incorporating water and water fragments into the catalyst's structure, they succeeded in enhancing its stability in acidic environments typical of PEM electrolyzers.


This breakthrough was made possible through a process called delamination. By treating a cobalt-tungsten oxide with basic aqueous solutions, the researchers were able to replace the tungsten oxides with water molecules and hydroxyl groups. This new material has shown remarkable performance in terms of stability and activity under industrial high current density conditions.

The results of this research have been published in Science, highlighting a collaboration between ICFO and several prestigious institutions, including the Institute of Chemical Research of Catalonia (ICIQ), the Catalan Institute of Nanoscience and Nanotechnology (ICN2), the French National Centre for Scientific Research (CNRS), Diamond Light Source, and the Institute of Advanced Materials (INAM).

Dr. Lu Xia, a lead co-author of the study, emphasizes the significance of this discovery: "We have achieved a current density of 1 A/cm², a significant milestone, with over 600 hours of stability at this density. This is a major breakthrough for iridium-free catalysts."

While this discovery represents a significant step towards the industrialization of green hydrogen production, challenges remain, particularly the catalyst's lifespan and material optimization. The team is already working on nickel and manganese-based alternatives to further improve performance and durability.

By filing a patent for this new technology, the researchers hope to accelerate its industrial adoption, thus contributing to the decarbonization of our society and the transition to cleaner renewable energies.