Modeling adsorption of organic compounds (OCs) by carbon nanotubes (CNTs): role of OCs and CNTs properties on the linear solvation energy relationships (LSER)

This study evaluated a comprehensive database for the adsorption of polar and nonpolar organic compounds (OCs) by carbon nanotubes (CNTs) and to use the linear solvation energy relationship (LSER) technique for developing predictive adsorption models of OCs by multi-walled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs). The results showed that coefficient of determinations (R2) values for all compounds are higher variability in the 200 g/mol molecular weight cutoff (74–99%). When the molecular weight cutoff of all OCs is higher than 200 g/mol, the trend of their R2 values is decreased (less than 70%). Among all adsorbate descriptor coefficients, V and B terms are the most significant descriptors (p values ≤ 0.05) in LSER equations for adsorption of low molecular weight polar and nonpolar OCs by both CNTs. Besides, KOW normalization of all Kd values did not have significant impact on the regression of the LSER model, indicating that hydrophobic interactions are not sole mechanism for the adsorption of OCs on CNTs. Lastly, SWCNTs exhibited higher polar OCs uptake than MWCNTs, which was attributed to more polar surface of SWCNTs as suggested by its high oxygen content (%10).

Probing Solvation Effects in Binary Solvent Mixtures with the Use of Solvatochromic Dyes

In this work three molecules exhibiting dual sensing solvatochromic behaviors are examined in the context of solvation in binary solvent mixtures (BSMs). The compounds studied involve two functional groups with high responsiveness to solvent polarity namely pentacyanoferrate(II) (PC) and azo groups. Two of these compounds are [2]rotaxanes involving alpha- or beta- cyclodextrin (CyD) and the third is their CyD-free precursor. The dual solvatochromic behavior of these compounds is investigated in water/ethlylene glycol (EG) mixtures and their dual solvatochromic responses are assessed in terms of the intensity of solvatochromism and the extent of preferential solvation. To achieve this the linear solvation model by Kamlet, Abboud and Taft [J. Organomet. Chem. 1983, 48, 2877–2887] and the two-phase model of solvation by Bagchi and coworkers [J. Phys. Chem. 1991, 95, 3311–3314] are employed. The influence of the presence or lack of CyD (alpha- or beta-) on these dual solvatochromic sensors is analyzed.

Ionic liquids: “normal” solvents or nanostructured fluids?

This review provides an overview of the literature from 2010 to the present day, covering the effect of ionic liquids (ILs) on organic reactivity. Two major viewpoints emerge, based on linear solvation energy relationships or nanostructure of ILs.

Linear solvation energy relationship development for adsorption of synthetic organic compounds by carbon nanomaterials: an overview of the last decade

The LSER models for adsorption of SOCs by CNMs profoundly depend on compound properties, adsorbent characteristics and the background solution.