Abstract
Single-atom catalysis has been a topic of increasing interest due to the potential for improved selectivity, reactivity, and catalyst cost. However, single-atom catalysts are still difficult to characterize under realistic reaction conditions, leading to controversy regarding the capabilities of single atoms and a need for model studies. Herein, we examine the reaction of methanol on single Pd atoms supported on Fe3O4(001) under ultrahigh vacuum conditions. On Pd-free Fe3O4(001), a small fraction of methanol is converted to formaldehyde through a methoxy intermediate at 516 K. The addition of single Pd atoms lowers the barrier to C-H bond cleavage by a factor of 2, resulting in formaldehyde desorption by 290 K. However, Pd atoms begin to sinter by 300 K in the presence of methanol, and Pd clusters do not exhibit the same chemistry. Single atoms significantly lower the barrier to the oxidation of methanol, although their stability remains an issue.
| Original language | English |
|---|---|
| Pages (from-to) | 10977-10982 |
| Number of pages | 6 |
| Journal | ACS Catalysis |
| DOIs | |
| State | Published - 2019 |
Funding
This work was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences and performed in EMSL, a national scientific user facility sponsored by the Department of Energy’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory (PNNL). PNNL is a multiprogram national laboratory operated for DOE by Battelle. Computational Resources were provided by a user proposal at the NERSC user facility located at Lawrence Berkley National Laboratory.
Keywords
- FeO(001)
- heterogeneous catalysis
- methanol
- palladium
- partial oxidation
- single-atom catalysis