Dynamic Heterogeneities in Liquid Mixtures Confined in Nanopores

Ramona Mhanna (1) , Pierre Catrou (1) , Sujeet Dutta (1) , Ronan Lefort (1) , Ilham Essafri (1) , Aziz Ghoufi (1) , Matthias Muthmann (2) , Michaela Zamponi (2) , Bernhard Frick (3) , Denis Morineau (1)

1 IPR - Institut de Physique de Rennes
2 FZJ - Forschungszentrum Jülich GmbH | Centre de recherche de Jülich | Jülich Research Centre
3 ILL - Institut Laue-Langevin

Binary liquid mixtures can exhibit nanosegregation, albeit being fully miscible and homogeneous at the macroscopic scale. This tendency can be amplified by geometrical nanoconfinement, leading to remarkable properties. This work investigates the molecular dynamics of tert-Butanol (TBA)-Toluene (TOL) mixtures confined in silica nanochannels by quasielastic neutron scattering and molecular dynamics simulation. It reveals a decoupling of the molecular motion of each constituent of the binary liquid, which can be followed independently by selective isotopic HD labelling. We argue that this behavior is the signature of spatially segregated dynamic heterogeneities, which are due to the recently established core-shell nanophase separation induced by mesoporous confinement.

Domaines: Matière Molle [cond-mat.soft]; Chimie théorique et/ou physique

Ramona Mhanna, Pierre Catrou, Sujeet Dutta, Ronan Lefort, Ilham Essafri, et al.. Dynamic Heterogeneities in Liquid Mixtures Confined in Nanopores. Journal of Physical Chemistry B, 2020, 124 (15), pp.3152-3162. ⟨10.1021/acs.jpcb.0c01035⟩. ⟨hal-02523643⟩