Abstract
The analogy between single-atom catalysts (SACs) and molecular catalysts predicts that the specific catalytic activity of these systems is constant. We provide evidence that this prediction is not necessarily true. As a case in point, we show that the specific activity over ceria-supported single Pd atoms linearly increases with metal atom density, originating from the cumulative enhancement of CeO2 reducibility. The long-range electrostatic footprints (≈1.5 nm) around each Pd site overlap with each other as surface Pd density increases, resulting in an observed deviation from constant specific activity. These cooperative effects exhaust previously active O atoms above a certain Pd density, leading to their permanent removal and a consequent drop in reaction rate. The findings of our combined experimental and computational study show that the specific catalytic activity of reducible oxide-supported single-atom catalysts can be tuned by varying the surface density of single metal atoms.
Original language | English |
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Pages (from-to) | 22769-22775 |
Number of pages | 7 |
Journal | Angewandte Chemie - International Edition |
Volume | 60 |
Issue number | 42 |
DOIs | |
State | Published - Oct 11 2021 |
Externally published | Yes |
Funding
We acknowledge the financial support from the National Research Foundation (NRF) (No. 2016R1A5A1009405, 2017R1A2B4007310). Work at the Pacific Northwest National Laboratory (PNNL) was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division. PNNL is a multiprogram national laboratory operated for DOE by Battelle under Contract DE-AC05-76RL01830. Computational Resources were provided by a user proposal at the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkley National Laboratory (LBNL). We acknowledge the financial support from the National Research Foundation (NRF) (No. 2016R1A5A1009405, 2017R1A2B4007310). Work at the Pacific Northwest National Laboratory (PNNL) was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division. PNNL is a multiprogram national laboratory operated for DOE by Battelle under Contract DE‐AC05‐76RL01830. Computational Resources were provided by a user proposal at the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkley National Laboratory (LBNL).
Funders | Funder number |
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U.S. Department of Energy | |
Battelle | DE‐AC05‐76RL01830 |
Office of Science | |
Basic Energy Sciences | |
Lawrence Berkeley National Laboratory | |
Chemical Sciences, Geosciences, and Biosciences Division | |
National Research Foundation of Korea | 2017R1A2B4007310, 2016R1A5A1009405 |
Keywords
- CO oxidation
- Pd/CeO
- electrostatic effects
- reducible oxide supports