Desulfurization-Related Surface Chemistry on Two-Dimensional Silica Films: Adsorption of Thiophene and Short-Chain Alkanes on Silicatene
Autor: | Uwe Burghaus, Nilushni Sivapragasam, M. T. Nayakasinghe |
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Rok vydání: | 2018 |
Předmět: |
Alkane
chemistry.chemical_classification Auger electron spectroscopy Thermal desorption spectroscopy 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials chemistry.chemical_compound General Energy Adsorption chemistry Electron diffraction Monolayer Thiophene Isobutane Physical chemistry Physical and Theoretical Chemistry 0210 nano-technology |
Zdroj: | The Journal of Physical Chemistry C. 122:8244-8253 |
ISSN: | 1932-7455 1932-7447 |
Popis: | The kinetics of thiophene and alkane adsorption on silicatene (i.e., on two-dimensional atomically thin and crystalline silica films) was studied by employing (multimass) thermal desorption spectroscopy (TDS) at ultrahigh vacuum. The monoatomic SiO2 film is grown on a Mo(112) support. Thiophene is a standard probe molecule for hydrodesulfurization (HDS); alkanes typically form as reaction products; Mo is a catalyst for HDS. The samples were characterized by Auger electron spectroscopy and low-energy electron diffraction as well as the silica film additionally by water TDS. The silicatene film is hydrophobic. All probe molecules adsorbed nondissociatively on silicatene. Two TDS peaks in the monolayer range are evident as well as a condensation structure. Thiophene binds with 42.6 ± 0.5 kJ/mol in the limit of zero coverage. Using a Redhead analysis and assumed pre-exponential of 1 × 1013/s, the (low coverage) binding energy of the alkanes (isobutane, n-pentane, and n-heptane) increases from 34.1 to 46.8 (±0... |
Databáze: | OpenAIRE |
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