Described as ‘a major breakthrough’ by Seoul National University (SNU)’s College of Engineering, the research was led by SNU’s Professor Jin Young Kim in collaboration with Professor Chan Woo Lee from Kookmin University and Dr Sung Jong Yoo from the Korea Institute of Science and Technology (KIST).
Detailed in Energy & Environmental Science, the catalyst features a ruthenium-based nanocluster with a core-shell structure. Despite using a minimal amount of precious metal, it is claimed to deliver ‘world-class performance’ and exceptional stability. Moreover, when applied to industrial-scale water electrolysis equipment, it demonstrated ‘remarkable efficiency’.
Anion Exchange Membrane Water Electrolysis (AEMWE) is gaining attention as a next-generation technology, but it requires catalysts that offer high efficiency and long-term stability for it to be commercially viable
Currently, platinum is the most widely used catalyst for hydrogen production, but its high cost and rapid degradation present significant challenges. While researchers have explored non-precious metal alternatives, these materials typically suffer from low efficiency and poor stability, making them unsuitable for industrial use.
To overcome these limitations, the research team developed a novel core-shell nanocluster catalyst based on ruthenium (Ru), which the team said is more than twice as cost-effective as platinum. By reducing the catalyst size to below 2nm and minimising the amount of precious metal to one-third, the new catalysts are said to have demonstrated 4.4 times higher performance than platinum catalysts with the same precious metal content.
Additionally, it recorded the highest performance ever reported among hydrogen evolution catalysts. Its foam electrode structure optimises the supply of reaction materials, ensuring stability even under high current densities.
In industrial-scale AEMWE testing, the new catalyst required less power compared to commercial platinum catalysts.
To develop the catalysts, the team first treated a titanium foam substrate with hydrogen peroxide to form a thin titanium oxide layer. This was followed by doping with the transition metal molybdenum. Next, ruthenium oxide nanoparticles measuring 1–2nm were uniformly deposited on the modified substrate.
A precise low-temperature thermal treatment induced atomic-level diffusion, forming the core-shell structure. During the hydrogen evolution reaction, an electrochemical reduction process further enhanced the material’s properties, resulting in a ruthenium metal core encapsulated by a porous reduced titania monolayer, with metallic molybdenum atoms positioned at the interface.
According to the team, the catalyst’s combination of high performance and economic feasibility makes it suitable for use in hydrogen fuel cells for vehicles, eco-friendly transportation systems, hydrogen power plants, and various industrial applications.
In a statement, Professor Jin Young Kim, from the Department of Materials Science and Engineering at SNU, said: “The core-shell catalyst, despite being smaller than 2nm, demonstrates remarkable performance and stability. This breakthrough will contribute significantly to the development of nano core-shell device fabrication technology and hydrogen production, bringing us closer to a carbon-neutral future.”