A research team at Seoul National University led by Professor Jin Young Kim has made a significant breakthrough in eco-friendly hydrogen production by developing a ruthenium-based nanocluster catalyst with a core-shell structure. This catalyst, which contains only one-third the amount of precious metal compared to conventional platinum-based electrodes, demonstrated exceptional performance and stability in industrial-scale water electrolysis systems. Published in Energy & Environmental Science, the study highlights the catalyst's remarkable efficiency, surpassing that of existing platinum catalysts. By optimizing the catalyst size and minimizing precious metal usage, the team achieved record-breaking performance in hydrogen evolution reaction efficiency, setting a new benchmark in the field. The core-shell nanocluster catalyst showed superior stability even under high current densities and required less power in AEMWE testing compared to commercial platinum catalysts, indicating its potential for commercial use. The development process involved several key innovations, including atomic-level engineering to enhance functionality. The catalyst's unique foam electrode structure optimizes the supply of reaction materials, further improving its performance. This breakthrough not only offers a cost-effective and efficient solution for hydrogen production but also paves the way for a hydrogen-driven economy, with applications in fuel cells, transportation systems, power plants, and industrial processes. The core-shell catalyst's high performance and economic feasibility position it as a promising candidate for advancing sustainable hydrogen technologies and accelerating the transition towards a carbon-neutral future.