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Title: Adsorption of n-butane on graphene/Ru(0001)—A molecular beam scattering study

Abstract

Adsorption kinetics/dynamics of n-butane on graphene, physical vapor deposited on Ru(0001) (hereafter G/Ru), and bare Ru(0001) (hereafter Ru) are discussed. The chemical activity of the supported-graphene as well as the support was probed by thermal desorption spectroscopy (adsorption kinetics). In addition and to the best of our knowledge, for the first time, molecular beam scattering data of larger molecules were collected for graphene (probing the adsorption dynamics). Furthermore, samples were inspected by x-ray photoelectron spectroscopy and Auger electron spectroscopy. At the measuring conditions used here, n-butane adsorption kinetics/dynamics are molecular and nonactivated. Binding energies of butane on Ru and G/Ru are indistinguishable within experimental uncertainty. Thus, G/Ru is “kinetically transparent.” Initial adsorption probabilities, S{sub 0}, of n-butane decrease with increasing impact energy (0.76–1.72 eV) and are adsorption temperature independent for both Ru and G/Ru, again consistent with molecular adsorption. Also, S{sub 0} of Ru and G/Ru are indistinguishable within experimental uncertainty. Thus, G/Ru is “dynamically transparent.” Coverage dependent adsorption probabilities indicate precursor effects for graphene/Ru.

Authors:
; ;  [1]
  1. Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108 (United States)
Publication Date:
OSTI Identifier:
22592860
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 4; Other Information: (c) 2016 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ADSORPTION; AUGER ELECTRON SPECTROSCOPY; BINDING ENERGY; BUTANE; DESORPTION; GRAPHENE; KINETICS; MOLECULAR BEAMS; RUTHENIUM; SCATTERING; THERMODYNAMIC ACTIVITY; VAPOR DEPOSITED COATINGS; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Sivapragasam, Nilushni, Nayakasinghe, Mindika T., and Burghaus, Uwe, E-mail: uwe.burghaus@ndsu.edu. Adsorption of n-butane on graphene/Ru(0001)—A molecular beam scattering study. United States: N. p., 2016. Web. doi:10.1116/1.4954811.
Sivapragasam, Nilushni, Nayakasinghe, Mindika T., & Burghaus, Uwe, E-mail: uwe.burghaus@ndsu.edu. Adsorption of n-butane on graphene/Ru(0001)—A molecular beam scattering study. United States. doi:10.1116/1.4954811.
Sivapragasam, Nilushni, Nayakasinghe, Mindika T., and Burghaus, Uwe, E-mail: uwe.burghaus@ndsu.edu. 2016. "Adsorption of n-butane on graphene/Ru(0001)—A molecular beam scattering study". United States. doi:10.1116/1.4954811.
@article{osti_22592860,
title = {Adsorption of n-butane on graphene/Ru(0001)—A molecular beam scattering study},
author = {Sivapragasam, Nilushni and Nayakasinghe, Mindika T. and Burghaus, Uwe, E-mail: uwe.burghaus@ndsu.edu},
abstractNote = {Adsorption kinetics/dynamics of n-butane on graphene, physical vapor deposited on Ru(0001) (hereafter G/Ru), and bare Ru(0001) (hereafter Ru) are discussed. The chemical activity of the supported-graphene as well as the support was probed by thermal desorption spectroscopy (adsorption kinetics). In addition and to the best of our knowledge, for the first time, molecular beam scattering data of larger molecules were collected for graphene (probing the adsorption dynamics). Furthermore, samples were inspected by x-ray photoelectron spectroscopy and Auger electron spectroscopy. At the measuring conditions used here, n-butane adsorption kinetics/dynamics are molecular and nonactivated. Binding energies of butane on Ru and G/Ru are indistinguishable within experimental uncertainty. Thus, G/Ru is “kinetically transparent.” Initial adsorption probabilities, S{sub 0}, of n-butane decrease with increasing impact energy (0.76–1.72 eV) and are adsorption temperature independent for both Ru and G/Ru, again consistent with molecular adsorption. Also, S{sub 0} of Ru and G/Ru are indistinguishable within experimental uncertainty. Thus, G/Ru is “dynamically transparent.” Coverage dependent adsorption probabilities indicate precursor effects for graphene/Ru.},
doi = {10.1116/1.4954811},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 4,
volume = 34,
place = {United States},
year = 2016,
month = 7
}
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