Property Changes of Multiphasic Fluids by Geometrical Confinement in Advanced Mesoporous Materials – NanoLiquids

========= Porous materials ================
Synthesis: molecular chemistry of bis-silylated precursors, hydrothermal chemistry.
Characterization of structure, porosity and surface interaction (XRD, NMR, DTA, GP, SEM, TEM, DVS, SANS).
=========Bulk and Confined liquids ================
Phase behavior (DSC, XRD)
Structure (SANS, WANS, Raman, MD)
Dynamics (QENS, BDS, MD)
Gas solubility (MSB)
Fluid Flow (SIA)
================Main equipment used ================
XRD: Wide-Angle X-ray diffractometer, TG/DTA/MS: Simultaneous thermal analysis, GP: Gas physisorption with different adsorptives (N2, Ar, H2O), DVS: Dynamical Vapor Sorption, SANS: Small Angle Neutron Scattering, WANS: Wide Angle Neutron Diffractometer, DSC: Differential Scanning Calorimetry, MD: Molecular Dynamics Simulation, BDS: Broadband Dielectric Spectroscopy, QENS: Quasielastic Neutron Scattering, MSB: Magnetic suspension balance, SIA: Optofluidic Spontaneous Imbibition Apparatus

================Advanced mesoporous hosts ================
Series of bis-silylated precursors were synthesized, and successfully transformed into PMOs. Combined with MCM-41 and SBA-15 silicates, the consortium shared a set of characterized (by XRD, BET, DVS) advanced porous materials with different periodic modulations of the surface interactions (hydrophilic/hydrophobic/H-bonded).
====Derivation of force field and models for MD simulation=====
A methodology to derive a force field for PMO materials was developed. We applied a mimetic polymerisation process of the organic and the inorganic parts. It was optimized for divinylbenzene PMOs, also studied experimentally.
========Nanoconfined liquids========
1. Water confined in silicates and PMOs: A full set of experiments were conducted to assess the adsorption and surface interaction (DVS), phase behavior (DSC) and dynamics (QENS, BDS). Notably, QENS experiments were jointly conducted by the 3 partners at the ILL European neutron facility. In addition, preliminary QENS experiments on the water dynamics in surface-oxidised mesoporous silicon membranes have been conducted at the ILL.

2. t-Butanol-Toluene in silicates and PMOs: Beyond approaches also applied for water, we additionally focused on the possible formation of structural and dynamical nanoscale heterogeneities due to the nanosegregation of the two constituents. This phenomenon was confirmed structurally by SANS and also dynamically by QENS performed at ILL.

====Aqueous solutions====
Exciting new results obtained either in the bulk state or in confining porous silicates confirmed that they were also excellent candidates for further studies in PMOs. Especially cryoscopic agents (such as glycerol) showed strong deviations from the theoretical predictions of classical thermodynamics, suggesting a variation of the water activity due to spatial segregation. Such a phenomenon might be enhanced in PMOs. In addition to cryoscopic agents, aqueous mixtures of H-bonded and molecular ions, falling in the category of Deep Eutectic Solvents will be considered in confinement after the inspiring results that we obtained in the bulk.

Press release INP – CNRS Oct. 2020
Articles:
A. Jani, T. Sohier, D. Morineau, J. Mol. Liq., 2020, 304, pp.112701
B. Malfait, A. Pouessel, A. Jani, D. Morineau, J. Phys. Chem. Lett., 2020, 11 (14), pp.5763-5769
L. Percevault, A. Jani, T. Sohier, L. Noirez, L. Paquin, F. Gauffre, D. Morineau, J. Phys. Chem B, 2020, 124 (41), pp. 9126-9135

Conference:
InterPore2020, 31 Aug.-4 Sept. 2020 “Dynamic Heterogeneities in Liquid Mixtures Confined in Nanopores” A. JANI, R. MHANNA, B. MIETNER, M. BUSCH, B. FRICK, J.-M. ZANOTTI, A. GHOUFI, P. HUBER, M. FRÖBA, D. MORINEAU
InterPore2020, 31 Aug.-4 Sept. 2020 “Water Dynamics in Nanoporous Confinement: A Quasielastic Neutron Scattering Study” A. JANI, B. MIETNER, M. BUSCH, J. OLLIVIER, B. FRICK, M. APPEL, J.-M. ZANOTTI, P. HUBER, M. FRÖBA, D. MORINEAU
InterPore2019, 6-10 May 2019, Valencia, Espagne “Binary solvents in nanoporous confinement: how different are they?” D. Morineau; A. Jani; R. Mhanna; S. Dutta; R. Lefort; I. Essafri; A. Ghoufi; P. Huber; M. Froba; B. Frick; L. Noirez
« Binary solvents in nanoporous confinement: how different are they? », D. Morineau, May 2019, Invited at the Chalmer University, Goteborg (Sweden).
Journées de la Diffusion Neutronique 2019, 16-19 Sept. 2019 Saint-Martin-de-Londres “Toluene/butanol binary solvents confined in periodic organosilicates”, A. JANI, B. MIETNER, V. CRISTIGLIO, P. HUBER, M.FRÖBA, D. MORINEAU
« Nanoconfined liquids », D. Morineau, May 2019, Keynote lecture at The SFNano C’Nano meeting, 10-12 Décembre 2019, Dijon
Journées Scientifiques du GDR 2035 SolVATE, 4-5 Feb. 2019, Lyon “Toluene/Butanol Binary Solvents Confined in Periodic Organosilicates: New Insight From Neutron Diffraction Studies”, A. JANI, B. MIETNER, V. CRISTIGLIO, P.HUBER, M. FRÖBA, D. MORINEAU
JNano19, 13-15 Feb. Rennes “Toluene/Butanol Binary Solvents Confined in Periodic Organosilicates: New Insight From Neutron Diffraction Studies”, A. JANI, B. MIETNER, V. CRISTIGLIO, P. HUBER, M. FRÖBA, D. MORINEAU

Fluids confined in nanometer-size porous geometry exhibit unique properties that have no equivalent in the corresponding bulk systems. As such, they deserve an extensive interest for their high potential of technological innovation. In this context, the scientific community has been encouraged to improve the ground basis knowledge of nanoconfined liquids.
During the last decade, an impressive number of physico-chemical properties have been studied when confining a fluid in a mesoporous medium. As a whole, it appears that the nature of the surface-liquid interaction and the geometric parameters of confinement readily affect the phase behavior, structure, dynamics and fluid flow, leading to original physico-chemical phenomena.

The next step in the field would be to direct the (new) properties of nanofluids in a desired manner. Many of the studied systems comprised a single fluid phase confined in a ‘passive’ porous material, which is seen as a bottleneck to such developments. For this reason, the intension of the NanoLiquids project, is to explore the properties of new systems that would allow for an unprecedented control of interfaces based on the nanoconfinement of multicomponent fluids into functionalized porous materials with periodically alternating surface chemistry.

Starting from examinations of the mesoscale structure and dynamics of the bulk binary systems the physico-chemical properties of mixtures confined in tailored mesoporous media shall be explored. In particular effects such as microphase separation, enhanced gas solubility and confinement-induced changes in the fluid rheology as well as the interplay of these phenomenologies will be in the research focus. These studies will be possible only by the combination of an extensive number of complementary methods and skills in physics and chemistry, both experimental and numerical, encompassing temporal and spatial windows that range from the molecular to the macroscopic scales and provide a strong added value to the proposed French-German collaboration.