Seoul National University (SNU) College of Engineering announced that a research team led by Professor Jeong Woo Han of the Department of Materials Science and Engineering has developed a new nanostructured catalyst with up to 14.4 times higher greenhouse gas decomposition performance compared to conventional commercial catalysts.
The research team synthesized a new nanostructure, termed “nanomace,” by chemically bonding ceria (CeO₂) nanocubes and nanorods. They revealed that the boundary where the two crystal structures meet serves as a key active site where catalytic reactions occur most actively.
The nanomace catalyst reduces the use of expensive precious metals typically required to enhance catalytic performance, while offering broad applicability in automobile exhaust purification, industrial emission reduction, greenhouse gas removal, and clean hydrogen production. As such, it is expected to accelerate the commercialization of eco-friendly energy and environmental technologies.
The research findings were published in the prestigious international journal Nature Communications . Notably, the study was selected for the journal’s “Editors’ Highlight: Catalysis Focus” section, which features outstanding research in the field of catalysis.
Greenhouse gases are widely recognized as a major driver of increasingly severe extreme weather events, such as the record-breaking heatwaves recently observed in Europe. Catalytic technologies capable of decomposing harmful gases in automobile exhaust and industrial emissions, including greenhouse gases, are considered key eco-friendly solutions to address this global challenge.
A core material in such catalytic technologies is ceria (CeO₂), a metal oxide known as an “oxygen storage material” due to its excellent ability to store and release oxygen as needed. Ceria has been widely used as a critical material in oxidation–reduction reactions, including automotive exhaust purification, greenhouse gas reduction, and hydrogen production, where it can replace or complement costly precious metal catalysts.
Until now, ceria has typically been used in single morphologies such as nanocubes or nanorods, with nanorods generally considered to exhibit the highest catalytic performance. However, combining different ceria morphologies into a single chemically bonded structure to further enhance catalytic performance had not been previously explored.
Such structural design is important because catalytic performance is strongly influenced by reactions involving lattice oxygen*. In particular, for the Mars–van Krevelen (MvK) mechanism*—in which lattice oxygen at the catalyst surface directly participates in reactions—the nanostructural design principles required to maximize lattice oxygen activation have not yet been clearly established.
* Lattice oxygen: Oxygen atoms that form part of the crystal lattice of ceria and directly participate in catalytic reactions, such as decomposing harmful gases or oxidizing other substances.
* Mars – van Krevelen (MvK) mechanism: A catalytic mechanism in which lattice oxygen is consumed during the reaction and subsequently replenished by oxygen from the surrounding environment.
To address this, Professor Han’s team set out to develop a new structure that chemically integrates ceria nanocubes and nanorods and to elucidate how the irregular atomic arrangement at their interface enhances lattice oxygen activation.
As a result, the team successfully synthesized, for the first time, a nanomace catalyst in which ceria nanocubes and nanorods are chemically combined into a single structure. “This high-performance catalyst consists of a nanorod studded with cubic nanocubes—visually reminiscent of a spiked mace.”
* The name “nanomace” is derived from the medieval weapon “mace.”
The key factor determining the performance of the nanomace is the interface where the nanocube and nanorod meet. When the two distinct crystal structures are chemically bonded, the regular atomic arrangement at the boundary becomes disrupted, making it easier for lattice oxygen to be released and actively participate in catalytic reactions. In contrast, simply mixing nanocubes and nanorods does not produce this effect—chemical bonding is essential to enhance catalytic activity at the interface.
The team further demonstrated that although this interface constitutes only a small portion of the total surface, it acts as a “hidden workhorse,” accounting for approximately one-third of the overall catalytic reaction. Owing to this structure, the nanomace catalyst can activate oxygen and initiate catalytic reactions at lower temperatures than conventional single-structure ceria materials, including nanorods.
In addition, the researchers used artificial intelligence-based graph neural network (GNN) simulations to uncover, at the atomic level, why lattice oxygen at the interface more readily participates in catalytic reactions. Large-scale surface simulations showed that the interface is the region where oxygen vacancies are most easily formed, making it the most catalytically active site. Molecular dynamics simulations further confirmed the reaction process in which carbon monoxide interacts with lattice oxygen at the interface.
Through these findings, the team proposed a new catalyst design principle—“interface engineering”—which enhances catalytic performance by precisely designing the interface structure.
Another strength of the nanomace catalyst lies in its versatility across different catalytic reactions. When small amounts of precious metals such as gold (Au), palladium (Pd), and rhodium (Rh) were supported on the nanomace structure, the catalyst achieved up to 14.4 times higher performance than commercial catalysts across multiple reaction types. Gold-supported catalysts enabled hydrogen production via the water–gas shift reaction, while palladium- and rhodium-supported catalysts decomposed greenhouse gases such as methane and nitrous oxide (N₂O), respectively.
Moreover, gold-supported nanomace catalysts were able to remove carbon monoxide at extremely low temperatures of –70°C and maintained stable performance for over 150 hours, demonstrating strong potential for practical applications.
The nanomace catalyst developed in this study is expected to be widely applied not only in technologies for purifying harmful emissions from vehicles and industrial sources, but also in clean hydrogen production and carbon-neutral energy systems.
In particular, its ability to achieve high catalytic performance using only small amounts of precious metals offers strong economic advantages, making it a key technology for accelerating the commercialization of environmentally friendly catalysts.
Professor Jeong Woo Han stated,
“This study demonstrates that catalytic performance can be maximized by precisely controlling the morphology of the catalyst to enhance lattice oxygen activity. We expect this to serve as a universal catalyst design principle applicable to a wide range of oxidation–reduction reactions.”
Seokhyun Choung (postdoctoral researcher), Yunkyung Kim (Ph.D. candidate), and Myeong Gon Jang (Ph.D.) of the Department of Materials Science and Engineering at Seoul National University participated in this study as co-first authors. The research was conducted in collaboration with Sungkyunkwan University, POSTECH, Korea University of Technology and Education, and Japan’s SPring-8 facility.
□ Introduction to the SNU College of Engineering
Seoul National University (SNU) founded in 1946 is the first national university in South Korea. The College of Engineering at SNU has worked tirelessly to achieve its goal of ‘fostering leaders for global industry and society.’ In 12 departments, 323 internationally recognized full-time professors lead the development of cutting-edge technology in South Korea and serving as a driving force for international development.
Nature Communications
Experimental study
Not applicable
The authors declare no competing interests.