In a significant stride towards enhancing the efficiency and durability of proton exchange membrane (PEM) electrolyzers, a team of researchers from the University of Chemistry and Technology Prague, led by David Kolenatý and Jiří Čapek, has developed innovative coatings that could revolutionize the energy sector. Their work, published in the journal “Surface and Coatings Technology,” focuses on creating corrosion-resistant and conductive coatings for critical components in PEM electrolyzers, which are key devices for producing green hydrogen.
The researchers have successfully developed highly corrosion-resistant and conductive titanium-niobium-oxide (Ti-Nb-O) coatings for metallic components such as bipolar plates (BPPs) and porous transport layers (PTLs) in PEM water electrolyzers. These coatings are applied using a technique called reactive high-power impulse magnetron sputtering (HiPIMS), which allows for precise control over the coating’s composition and properties. By systematically tailoring the oxygen partial pressure and the ratio of niobium to titanium, the team can adjust the stoichiometry and structure of the coatings, directly influencing their electrical resistivity and corrosion resistance.
The optimized coatings exhibit remarkable properties, including electrical resistivity on the order of 10^-4 Ohmcm and extremely low corrosion current densities, well below the U.S. Department of Energy’s 2026 target. One of the most significant achievements is the ability to meet the interfacial contact resistance (ICR) target after accelerated corrosion testing with a platinum (Pt) overlayer as thin as 5 nm. This innovation reduces the platinum loading by up to two orders of magnitude compared to conventional approaches, which is a substantial advancement given the high cost and limited availability of platinum.
The practical applications of this research are profound for the energy sector, particularly in the realm of green hydrogen production. PEM electrolyzers are crucial for splitting water into hydrogen and oxygen using renewable electricity, and improving their efficiency and durability is essential for scaling up hydrogen production. The new coatings can enhance the performance and longevity of electrolyzers, making them more cost-effective and reliable. This, in turn, can accelerate the adoption of hydrogen as a clean energy carrier, contributing to the global transition towards sustainable energy solutions.
The research highlights the importance of materials science in driving technological advancements in the energy industry. By developing coatings that are both highly conductive and resistant to corrosion, the team has addressed key challenges in the operation of PEM electrolyzers. The reduced need for platinum not only lowers costs but also aligns with efforts to minimize the use of precious metals in energy technologies. As the world continues to seek innovative solutions to decarbonize the energy sector, such breakthroughs are pivotal in paving the way for a more sustainable future.
This article is based on research available at arXiv.