Ashley C. Cass
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Ashley C. Cass has a total of 6 co-authors. Here are the top co-authors by number of shared publications:
- Anastassia N. Alexandrova
University of California, Los Angeles
1 shared publication - Borna Zandkarimi
Department of Chemistry and Biochemistry University of California, Los Angeles 607 Charles E. Young Drive East Los Angeles CA 90095 USA
1 shared publication - Bradley J. Allen
Chemistry Department, University of Utah, Salt Lake City, Utah 84112, USA
1 shared publication - Guangjing Li
Chemistry Department, University of Utah, Salt Lake City, Utah 84112, USA
1 shared publication - Scott L. Anderson
Chemistry Department, University of Utah, 315 S. 1400 E., Salt Lake City, UT 84112, USA
1 shared publication - Timothy John Gorey
Los Alamos National Laboratory
1 shared publication
Latest Publications
- 8 January 2020
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 152 (2) , 024702
Sn-modification of Pt7/alumina model catalysts: Suppression of carbon deposition and enhanced thermal stability
An atomic layer deposition process is used to modify size-selected Pt7/alumina model catalysts by Sn addition, both before and after Pt7 cluster deposition. Surface science methods are used to probe the effects of Sn-modification on the electronic properties, reactivity, and morphology of the clusters. Sn addition, either before or after cluster deposition, is found to strongly affect the binding properties of a model alkene, ethylene, changing the number and type of binding sites, and suppressing decomposition leading to carbon deposition and poisoning of the catalyst. Density functional theory on a model system, Pt4Sn3/alumina, shows that the Sn and Pt atoms are mixed, forming alloy clusters with substantial electron transfer from Sn to Pt. The presence of Sn also makes all the thermally accessible structures closed shell, such that ethylene binds only by π-bonding to a single Pt atom. The Sn-modified catalysts are quite stable in repeated ethylene temperature programmed reaction experiments, suggesting that the presence of Sn also reduces the tendency of the sub-nano-clusters to undergo thermal sintering.
- 8 January 2020
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 152 (2) , 024702
Sn-modification of Pt7/alumina model catalysts: Suppression of carbon deposition and enhanced thermal stability
An atomic layer deposition process is used to modify size-selected Pt7/alumina model catalysts by Sn addition, both before and after Pt7 cluster deposition. Surface science methods are used to probe the effects of Sn-modification on the electronic properties, reactivity, and morphology of the clusters. Sn addition, either before or after cluster deposition, is found to strongly affect the binding properties of a model alkene, ethylene, changing the number and type of binding sites, and suppressing decomposition leading to carbon deposition and poisoning of the catalyst. Density functional theory on a model system, Pt4Sn3/alumina, shows that the Sn and Pt atoms are mixed, forming alloy clusters with substantial electron transfer from Sn to Pt. The presence of Sn also makes all the thermally accessible structures closed shell, such that ethylene binds only by π-bonding to a single Pt atom. The Sn-modified catalysts are quite stable in repeated ethylene temperature programmed reaction experiments, suggesting that the presence of Sn also reduces the tendency of the sub-nano-clusters to undergo thermal sintering.