Confinement Effects on Glass-Forming Aqueous Dimethyl Sulfoxide Solutions
Institute of Condensed Matter Physics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
*
Author to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Molecules 2020, 25(18), 4127; https://doi.org/10.3390/molecules25184127
Received: 11 August 2020
/
Revised: 4 September 2020
/
Accepted: 5 September 2020
/
Published: 9 September 2020
(This article belongs to the Special Issue Physical Chemistry of Aqueous Solutions and Glass Forming Systems)
Combining broadband dielectric spectroscopy and nuclear magnetic resonance studies, we analyze the reorientation dynamics and the translational diffusion associated with the glassy slowdown of the eutectic aqueous dimethyl sulfoxide solution in nano-sized confinements, explicitly, in silica pores with different diameters and in ficoll and lysozyme matrices at different concentrations. We observe that both rotational and diffusive dynamics are slower and more heterogeneous in the confinements than in the bulk but the degree of these effects depends on the properties of the confinement and differs for the components of the solution. For the hard and the soft matrices, the slowdown and the heterogeneity become more prominent when the size of the confinement is reduced. In addition, the dynamics are more retarded for dimethyl sulfoxide than for water, implying specific guest-host interactions. Moreover, we find that the temperature dependence of the reorientation dynamics and of the translational diffusion differs in severe confinements, indicating a breakdown of the Stokes–Einstein–Debye relation. It is discussed to what extent these confinement effects can be rationalized in the framework of core-shell models, which assume bulk-like and slowed-down motions in central and interfacial confinement regions, respectively.
View Full-Text
Keywords:
confinement; aqueous solutions; glass transition; molecular dynamics; broadband dielectric spectroscopy; nuclear magnetic resonance
▼
Show Figures
Figure 1
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
- Supplementary File 1:
PDF-Document (PDF, 110 KiB)
MDPI and ACS Style
Demuth, D.; Reuhl, M.; Hopfenmüller, M.; Karabas, N.; Schoner, S.; Vogel, M. Confinement Effects on Glass-Forming Aqueous Dimethyl Sulfoxide Solutions. Molecules 2020, 25, 4127. https://doi.org/10.3390/molecules25184127
AMA Style
Demuth D, Reuhl M, Hopfenmüller M, Karabas N, Schoner S, Vogel M. Confinement Effects on Glass-Forming Aqueous Dimethyl Sulfoxide Solutions. Molecules. 2020; 25(18):4127. https://doi.org/10.3390/molecules25184127
Chicago/Turabian StyleDemuth, Dominik, Melanie Reuhl, Moritz Hopfenmüller, Nail Karabas, Simon Schoner, and Michael Vogel. 2020. "Confinement Effects on Glass-Forming Aqueous Dimethyl Sulfoxide Solutions" Molecules 25, no. 18: 4127. https://doi.org/10.3390/molecules25184127
Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.
