Second harmonic scattering reveals different orientational orders inside the hydrophobic cavity of hybrid nanotubes.

Second Harmonic Scattering (SHS) is a suitable technique to investigate the orientational correlations between molecules. This article explores the organization of different dye molecules adsorbed within the hydrophobic porosity of a hybrid organic-inorganic nanotube. Experimental polarization resolved SHS measurements highlight different orientational orders ranking from highly ordered and rigid organizations to disordered assemblies.

Dried hybrid imogolite nanotubes as solids with a changeable surface area: an insight into textural properties based on the correlation between nitrogen gas adsorption, immersion calorimetry into water, and small angle X-ray scattering.

Powdered samples of three imogolite materials with an inner surface covered with Si-CH groups (hybrid IMO-CH) were prepared by ambient drying at 323 K, freeze drying, and spray drying. Reliable estimates of the intra-tube (), inter-tube (), and inter-bundle () specific surface areas of these samples were inferred from a model-guided correlation between the results of measurements by small angle X-ray scattering (SAXS), nitrogen gas adsorption, and immersion calorimetry into water. Since the SAXS studies indicated no significant deformations of IMO-CH nanotubes upon drying, further studies by gaseous N adsorption at 77 K indicated the intra-tube and inter-bundle specific surface areas as being only accessible to this adsorbate.

Renewing Interest in Zeolites as Adsorbents for Capture of Cationic Dyes from Aqueous and Ethanolic Solutions: A Simulation-Based Insight into the Efficiency of Dye Adsorption in View of Wastewater Treatment and Valorization of Post-Sorption Materials.

The impact of solvents on the efficiency of cationic dye adsorption from a solution onto protonated Faujasite-type zeolite (FAU-Y) was investigated in the prospect of supporting potential applications in wastewater treatment or in the preparation of building blocks for optical devices. The adsorption isotherms were experimentally determined for methylene blue (MB) and auramine O (AO) from single-component solutions in water and in ethanol. The limiting dye uptake (saturation capacity) was evaluated for each adsorption system, and it decreased in the order of MB-water > AO-water > AO-ethanol > MB-ethanol.

Hydrophobic dye solubilization hybrid imogolite nanotubes probed using second harmonic scattering.

This article explores the organization and interactions of Disperse Orange 3 (DO3) hydrophobic dye molecules within hybrid organic-inorganic imogolite nanotubes. In pure water, the DO3 dye molecules self assemble into large insoluble 2D nanosheets whose structure is also explored by molecular dynamics simulations. The dye molecules are however efficiently solubilized in the presence of hybrid imogolite nanotubes.

Water Organization around Inorganic Nanotubes in Suspension Probed by Polarization-Resolved Second Harmonic Scattering.

Imogolite nanotube (INT) is a fascinating one-dimensional (1D) material that can be synthesized in the liquid phase. Its behavior in solution is crucial for many applications and depends on the organization of water at the liquid-wall interface. We study here this water organization by using the nonlinear optical technique of polarization-resolved second harmonic scattering (SHS).

Driving Forces of Cationic Dye Adsorption, Confinement, and Long-Range Correlation in Zeolitic Materials.

Zeolitic materials are commonly used to capture emergent contaminants in water or complex aqueous effluents. The efficiency of this adsorption depends strongly on the guest-host interactions and on the surrounding environment with possible coadsorption of the solvent. Only a few experimental techniques are available to probe in situ the sequestration processes at the solid/liquid interface.

PySHS: Python Open Source Software for Second Harmonic Scattering.

The PySHS package is a new python open source software tool which simulates the second harmonic scattering (SHS) of different kinds of colloidal nano-objects in various experimental configurations. This package is able to compute polarizations resolved at a fixed scattered angle or angular distribution for different polarization configurations. This article presents the model implemented in the PySHS software and gives some computational examples.

Second-Harmonic Scattering in Layered Double Hydroxide Colloids: A Microscopic View of Adsorption and Intercalation.

The interaction of methyl orange dye with a layered double hydroxide colloidal material is investigated using real-time polarization-resolved second-harmonic scattering (SHS). Interlayer charge compensating anion exchange is studied from initial carbonate or nitrate anions to methyl orange negatively charged dye. A theoretical model, taking into account the field retardation effect, is presented to simulate the polarization-resolved SHS experiments.

Surface activity and molecular organization of metallacarboranes at the air-water interface revealed by nonlinear optics.

Because of their amphiphilic structure, surfactants adsorb at the water-air interface with their hydrophobic tails pointing out of the water and their polar heads plunging into the liquid phase. Unlike classical surfactants, metallabisdicarbollides (MCs) do not have a well-defined amphiphilic structure. They are nanometer-sized inorganic anions with an ellipsoidal shape composed of two carborane semicages sandwiching a metal ion.

Nonradiative deactivation of excited hemicyanines studied with submolecular spatial resolution by time-resolved surface second harmonic generation at liquid-liquid interfaces.

The excited-state dynamics of aminostilbazolium dyes is known to be dominated by nonradiative deactivation through large-amplitude motion. In order to identify the coordinate(s) responsible for this process, the excited-state lifetimes of two dialkylaminostyryl-methylpyridinium iodides have been measured at liquid-liquid interfaces using time-resolved surface second harmonic generation. We found that the decay time of the excited-states of both compounds was increasing with the viscosity of the apolar phase, consisting of n-alkanes of varying length, but was unaffected by that of the polar phase, made of water/glycerol mixtures.