Interface Chemistry and Molecular Bonding of Functional Ethoxysilane-Based Self-Assembled Monolayers on Magnesium Surfaces

Journal article


Publication Details

Author(s): Killian M, Seiler S, Wagener V, Hahn R, Ebensperger C, Meyer B, Schmuki P
Journal: ACS Applied Materials and Interfaces
Publication year: 2015
Volume: 7
Journal issue: 17
Pages range: 9006-9014
ISSN: 1944-8244
eISSN: 1944-8252
Language: English


Abstract


The modification of magnesium implants with functional organic molecules is important for increasing the biological acceptance and for reducing the corrosion rate of the implant. In this work, we evaluated by a combined experimental and theoretical approach the adsorption strength and geometry of a functional self-assembled monolayer (SAM) of hydrolyzed (3-aminopropyl)triethoxysilane (APTES) molecules on a model magnesium implant surface. In time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS), only a minor amount of reverse attachment was observed. Substrate–O–Si signals could be detected, as well as other characteristic APTES fragments. The stability of the SAM upon heating in UHV was investigated additionally. Density-functional theory (DFT) calculations were used to explore the preferred binding mode and the most favorable binding configuration of the hydrolyzed APTES molecules on the hydroxylated magnesium substrate. Attachment of the molecules via hydrogen bonding or covalent bond formation via single or multiple condensation reactions were considered. The impact of the experimental conditions and the water concentration in the solvent on the thermodynamic stability of possible APTES binding modes is analyzed as a function of the water chemical potential of the environment. Finally, the influence of van der Waals contributions to the adsorption energy will be discussed.



FAU Authors / FAU Editors

Ebensperger, Christina
Professur für Computational Chemistry
Hahn, Robert
Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)
Killian, Manuela Dr.-Ing.
Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)
Meyer, Bernd Prof. Dr.
Professur für Computational Chemistry
Schmuki, Patrik Prof. Dr.
Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)
Seiler, Steffen
Professur für Computational Chemistry
Wagener, Victoria
Professur für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)


Additional Organisation
Exzellenz-Cluster Engineering of Advanced Materials


Research Fields

D Catalytic Materials
Exzellenz-Cluster Engineering of Advanced Materials
A3 Multiscale Modeling and Simulation
Exzellenz-Cluster Engineering of Advanced Materials


How to cite

APA:
Killian, M., Seiler, S., Wagener, V., Hahn, R., Ebensperger, C., Meyer, B., & Schmuki, P. (2015). Interface Chemistry and Molecular Bonding of Functional Ethoxysilane-Based Self-Assembled Monolayers on Magnesium Surfaces. ACS Applied Materials and Interfaces, 7(17), 9006-9014. https://dx.doi.org/10.1021/am5075634

MLA:
Killian, Manuela, et al. "Interface Chemistry and Molecular Bonding of Functional Ethoxysilane-Based Self-Assembled Monolayers on Magnesium Surfaces." ACS Applied Materials and Interfaces 7.17 (2015): 9006-9014.

BibTeX: 

Last updated on 2019-15-05 at 10:33