skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

This content will become publicly available on October 23, 2020

Title: Atomic-Scale Surface Structure and CO Tolerance of NiCu Single-Atom Alloys

Abstract

Ni is one of the most extensively utilized metals in industrial catalysis. For example, Ni is the catalyst of choice for the steam reforming of hydrocarbons. However, pure Ni also detrimentally catalyzes the formation of graphitic carbon, which in turn leads to coking and deactivation of the catalyst. It has been shown that alloying small amounts of a less reactive metal like Au into Ni can alleviate this issue by breaking up the larger Ni ensembles that promote coke formation. We are taking the opposite of this approach by alloying very small amounts of Ni into Cu, another catalytically less active host metal to create single Ni atom sites. In this way our single-atom alloy approach has the potential to greatly enhance catalytic selectivity and reduce poisoning, analogous to other single-atom alloys such as PtCu and PdCu. Herein we report the atomic-scale surface structure and local geometry of low coverages of Ni deposited on a Cu(111) single crystal with scanning tunneling microscopy. At 433 K, low concentrations of Ni alloy in the Cu host as a single-atom alloy in Ni-rich brims along ascending step edges. To support our STM assignments of the single atom dispersion of Ni, reflection absorption infraredmore » spectroscopy of CO on NiCu was performed. To access the binding strength of CO to isolated Ni sites, we use temperature-programmed desorption studies which reveal that CO binds more weakly to single Ni atoms in Cu compared to Ni(111), indicating that NiCu single-atom alloys are promising for catalytic applications in which CO poisoning is an issue. Altogether, these results provide a guide for the preparation of NiCu single-atom alloy model catalysts that are predicted by theory to be promising for a number of reactions.« less

Authors:
 [1];  [1];  [1];  [1];  [1]; ORCiD logo [1]
  1. Tufts Univ., Medford, MA (United States)
Publication Date:
Research Org.:
Harvard Univ., Cambridge, MA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1595414
Grant/Contract Number:  
SC0012573
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. C
Additional Journal Information:
Journal Volume: 123; Journal Issue: 46; Journal ID: ISSN 1932-7447
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Desorption; Alloys; Catalysts; Deposition; Scanning tunneling microscopy

Citation Formats

Patel, Dipna A., Hannagan, Ryan T., Kress, Paul L., Schilling, Alex C., Çınar, Volkan, and Sykes, E. Charles H. Atomic-Scale Surface Structure and CO Tolerance of NiCu Single-Atom Alloys. United States: N. p., 2019. Web. doi:10.1021/acs.jpcc.9b07513.
Patel, Dipna A., Hannagan, Ryan T., Kress, Paul L., Schilling, Alex C., Çınar, Volkan, & Sykes, E. Charles H. Atomic-Scale Surface Structure and CO Tolerance of NiCu Single-Atom Alloys. United States. doi:10.1021/acs.jpcc.9b07513.
Patel, Dipna A., Hannagan, Ryan T., Kress, Paul L., Schilling, Alex C., Çınar, Volkan, and Sykes, E. Charles H. Wed . "Atomic-Scale Surface Structure and CO Tolerance of NiCu Single-Atom Alloys". United States. doi:10.1021/acs.jpcc.9b07513.
@article{osti_1595414,
title = {Atomic-Scale Surface Structure and CO Tolerance of NiCu Single-Atom Alloys},
author = {Patel, Dipna A. and Hannagan, Ryan T. and Kress, Paul L. and Schilling, Alex C. and Çınar, Volkan and Sykes, E. Charles H.},
abstractNote = {Ni is one of the most extensively utilized metals in industrial catalysis. For example, Ni is the catalyst of choice for the steam reforming of hydrocarbons. However, pure Ni also detrimentally catalyzes the formation of graphitic carbon, which in turn leads to coking and deactivation of the catalyst. It has been shown that alloying small amounts of a less reactive metal like Au into Ni can alleviate this issue by breaking up the larger Ni ensembles that promote coke formation. We are taking the opposite of this approach by alloying very small amounts of Ni into Cu, another catalytically less active host metal to create single Ni atom sites. In this way our single-atom alloy approach has the potential to greatly enhance catalytic selectivity and reduce poisoning, analogous to other single-atom alloys such as PtCu and PdCu. Herein we report the atomic-scale surface structure and local geometry of low coverages of Ni deposited on a Cu(111) single crystal with scanning tunneling microscopy. At 433 K, low concentrations of Ni alloy in the Cu host as a single-atom alloy in Ni-rich brims along ascending step edges. To support our STM assignments of the single atom dispersion of Ni, reflection absorption infrared spectroscopy of CO on NiCu was performed. To access the binding strength of CO to isolated Ni sites, we use temperature-programmed desorption studies which reveal that CO binds more weakly to single Ni atoms in Cu compared to Ni(111), indicating that NiCu single-atom alloys are promising for catalytic applications in which CO poisoning is an issue. Altogether, these results provide a guide for the preparation of NiCu single-atom alloy model catalysts that are predicted by theory to be promising for a number of reactions.},
doi = {10.1021/acs.jpcc.9b07513},
journal = {Journal of Physical Chemistry. C},
number = 46,
volume = 123,
place = {United States},
year = {2019},
month = {10}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on October 23, 2020
Publisher's Version of Record

Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

Save / Share: