2025 AIChE Annual Meeting

(495f) Nanosocket Catalysts for Stable and Efficient Sustainable Redox Reactions

Authors

Taein Lee, Seoul National University
Redox reactions such as dry methane reforming (DRM) and CO oxidation are central to clean energy conversion and sustainable emission control. Exsolution catalysts offer high thermal stability and strong metal–support interaction, but their catalytic activity is often limited by low surface dispersion and limited control over active sites. To address these limitations, we introduce a nanosocket catalyst design in which immobile exsolved nanoparticles serve as anchoring sockets, and isolated Pt atoms are added on top—like a “cherry on top”—to enhance both activity and durability.

In Pt–Niexs/CeO2, Pt deposited on embedded Ni particles enables high catalytic activity and stability in DRM, outperforming Pt/CeO2 and other reported Ni-based catalysts. The system maintains CH4 and CO2 conversion under extended high-temperature DRM operation (> 800 °C), demonstrating potential for practical deployment in industrial environments. In Pt–Coexs/CeO2, the catalyst shows equal or higher activity than Pt/CeO2 for CO oxidation, achieving a T20 of ~80 °C and approaching equilibrium conversion. Synchrotron and in situ IR spectroscopy confirm the formation of Pt–Co interfacial sites, absent in Pt/CoOX references, as the origin of this high activity. The catalyst also retains its structure and CO oxidation conversion under wet conditions, supporting its suitability for three-way catalysis.

To identify the role of nanosockets and Pt active sites, molecular dynamics simulations are conducted using a graph neural network potential. Dynamic activation of reactants at Pt–metal interfaces was identified as the key mechanism driving high activity in both DRM and CO oxidation. This work establishes nanosocket catalysts with Pt decoration as a robust and scalable platform for high-efficiency redox catalysis, offering strong potential for sustainable, real-world energy and emission solutions.