Carbon monoxide enables rapid atomic scale control for fuel cell catalysts

by Riko Seibo
Tokyo, Japan (SPX) Dec 04, 2025
Researchers at the Korea Institute of Energy Research report a carbon monoxide driven process that forms metal thin films about 0.3 nanometers thick, enabling faster fabrication of core-shell fuel cell catalysts that reduce platinum usage while maintaining performance. The approach, called CO Adsorption-Induced Deposition, leverages the redox behavior and strong surface affinity of carbon monoxide to deposit atomically controlled platinum shells on low cost metal cores without additional reducing agents or electrochemical systems.

Core-shell catalysts place a thin platinum shell over a different metal core to achieve high oxygen reduction reaction activity with less platinum, improving fuel cell economics. The new process adsorbs a single molecular layer of CO on the core surface and then selectively reduces platinum onto that layer to control shell thickness at approximately 0.3 nanometers.

The method reduces processing time to 30 minutes to 2 hours at kilogram scale, compared with more than 24 hours for conventional copper underpotential deposition routes that require tight voltage control and oxide removal steps. By avoiding these steps, CO AID simplifies production while retaining atomic layer precision needed for high performance shells.

Using CO AID, the team coated platinum onto palladium, gold, and iridium cores. A palladium based platinum core-shell catalyst achieved about double the oxygen reduction reaction activity and 1.5 times the durability compared with commercial platinum on carbon benchmarks. The work was conducted with Brookhaven National Laboratory and published on Nov 7, 2025 in ACS Nano, with support from the Ministry of Science and ICT.

Lead researcher Gu-Gon Park said, "This work originated from the idea of converting carbon monoxide's toxicity into a tool for nanoscale thin-film control. By allowing materials to be precisely engineered at the atomic level and drastically reducing processing time, the technology presents a new synthesis paradigm with excellent prospects for commercialization."

Team member Yongmin Kwon added, "Being able to manipulate the surfaces of metal nanoparticles at the atomic-layer scale using something as simple as carbon monoxide means this technology could have far-reaching implications-not only for fuel-cell catalyst production, but also for advancing nanoparticle manufacturing in areas such as semiconductors and thin-film materials."

Research Report:CO Adsorption-Induced Depositon: A Facile and Precise Synthesis Route for Core-Shell Catalysts