Abstract
Nanoparticle-supported Pt and Pd catalysts are employed industrially to convert CO and hydrocarbon residue from incomplete diesel fuel combustion into more environmentally-benign products. However, these catalysts deactivate over time due to sintering, especially for Pt nanoparticles which readily generate volatile species under high operating temperatures. Here, we turned the detrimental vapor-mediated sintering of Pt into an advantage by using a physical mixture of Pt and Pd catalysts prepared using a raspberry-colloid-templating (RCT) method. The RCT method produced Pt/Al2O3 and Pd/Al2O3 catalysts with partially embedded NPs to inhibit surface-mediated sintering pathways. As validated using an industry-defined emission control test protocol, aging a physical mixture of Pt/Al2O3 and Pd/Al2O3 at high temperature produced an alloyed PtPd/Al2O3 catalyst that outperformed the fresh catalyst mixture and both individual catalysts for hydrocarbon conversion, while exhibiting high catalytic stability and resistance to sintering and to SO2 poisoning. X-ray photoelectron spectroscopy revealed that in the aged catalyst mixture, half of the Pd content existed in the more active metallic state, compared to the less active oxide forms in the fresh mixture and both individual catalysts, explaining the unusual activity enhancement. Our results represent a practical approach to producing active and stable PtPd/Al2O3 diesel oxidation catalysts for emission control applications.
| Original language | English |
|---|---|
| Article number | e202500295 |
| Journal | ChemSusChem |
| Volume | 18 |
| Issue number | 11 |
| DOIs | |
| State | Published - Jun 2 2025 |
Funding
This work was supported by the U.S. Defense Threat Reduction Agency (DTRA) under Award Number HDTRA12110016 and the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award Number DE-SC0012573. Work at Applied Catalysis and Emissions Research Group, Oak Ridge National Laboratory was supported by U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office (Program Managers: Gurpreet Singh, Ken Howden, Nicholas Hansford, and Siddiq Kahn). Electron microscopy and XPS analyses were performed at the Center for Nanoscale Systems (CNS), a member of the National Nanotechnology Coordinated Infrastructure Network (NNCI), which is supported by the National Science Foundation under NSF ECCS award 1541959. K.R.G.L. acknowledges financial support from the Agency for Science, Technology and Research (A*STAR) Singapore National Science Scholarship (PhD). Notice: This manuscript has been co-authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). This work was supported by the U.S. Defense Threat Reduction Agency (DTRA) under Award Number HDTRA12110016 and the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award Number DE‐SC0012573. Work at Applied Catalysis and Emissions Research Group, Oak Ridge National Laboratory was supported by U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office (Program Managers: Gurpreet Singh, Ken Howden, Nicholas Hansford, and Siddiq Kahn). Electron microscopy and XPS analyses were performed at the Center for Nanoscale Systems (CNS), a member of the National Nanotechnology Coordinated Infrastructure Network (NNCI), which is supported by the National Science Foundation under NSF ECCS award 1541959. K.R.G.L. acknowledges financial support from the Agency for Science, Technology and Research (A*STAR) Singapore National Science Scholarship (PhD). Notice: This manuscript has been co‐authored by UT‐Battelle, LLC under Contract No. DE‐AC05‐00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non‐exclusive, paid‐up, irrevocable, world‐wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe‐public‐access‐plan).
Keywords
- Alloys
- Catalyst stability
- Diesel oxidation catalyst
- Emission control
- Ostwald ripening
- Palladium
- Platinum