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NiAu Single Atom Alloys for the Non-oxidative Dehydrogenation of Ethanol to Acetaldehyde and Hydrogen
| Content Provider | United States Department of Energy Office of Scientific and Technical Information (OSTI.GOV) |
|---|---|
| Author | Giannakakis, Georgios Trimpalis, Antonios Shan, Junjun Qi, Zhen Cao, Sufeng Liu, Jilei Ye, Jianchao Flytzani-Stephanopoulos, Maria |
| Organization | Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States) |
| Abstract | Gold is examined here as an alternative to copper for the selective dehydrogenation of ethanol to acetaldehyde and hydrogen. Despite its high selectivity, gold is only active at temperatures higher than 250 °C for this reaction. We demonstrate that addition of a small amount of Ni on either supported or unsupported Au surfaces induces resistance to sintering, along with a beneficial effect on the catalytic activity. NiAu alloys prepared here with Ni as the minority component to the limit of atomic dispersion in the gold surfaces, catalyze the reaction beginning below 150 °C. A significant decrease of the apparent activation energy from 96 ± 3 kJ/mol for the monometallic Au to 59 ± 5 kJ/mol for the alloy was found. The Ni dispersion and concentration as a function of gas environment was followed by in situ DRIFTS and by XPS. The stability of the catalyst morphology was investigated through post-reaction microscopy imaging and long-term stability tests under reaction conditions. As shown via dynamic reaction experiments, acetaldehyde and H2 were selectively produced up to 280 °C. A small drop of selectivity at higher temperatures is attributed to the formation of Ni clusters, as proven by CO-DRIFTS on the used sample. Comparison with samples of higher Ni loading, where Ni clusters are formed, clearly shows that they catalyze the undesired full decomposition of ethanol to CO, CH4, and H2. |
| Sponsorship | USDOE National Nuclear Security Administration (NNSA) |
| Related Links | https://www.osti.gov/biblio/1502035 |
| Starting Page | 475 |
| Ending Page | 486 |
| Page Count | 12 |
| File Format | |
| ISSN | 10225528 |
| DOI | 10.1007/s11244-017-0883-0 |
| Journal | Topics in Catalysis |
| Volume Number | 61 |
| Issue Number | 5-6 |
| Language | English |
| Publisher | Springer |
| Publisher Date | 2018-03-19 |
| Publisher Place | United States |
| Access Restriction | Open |
| Subject Keyword | MATERIALS SCIENCE INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Single atom alloys Nickel Gold Ethanol dehydrogenation Acetaldehyde Hydrogen |
| Content Type | Text |
| Resource Type | Article |
| Subject | Chemistry Catalysis |
