This work reports on the preparation of cross-linked amine-alcohol-silicate hybrid matrixes with tunable hydrophilic/hydrophobic domains from end-group functionalized polyetheramines (PEO and PPO) and 3glycidoxypropyl-trimethoxysilane (GPMS) by the sol-gel route as efficient adsorbents for retaining anionic species; the resulting hybrid matrixes were designated as PEO500-GPMS and PPO400-GPMS, respectively. This work also discusses how the nature and swelling properties of the polyethers PEO and PPO, investigated by small-angle X-ray scattering (SAXS) and in situ SAXS measurements, affect the way PEO500-GPMS and PPO400-GPMS interact with the anionic dye, Rose Bengal (RB). The use of polyetheramines of different polyether nature afforded hybrid matrixes with distinct capacity and mechanisms of anionic species adsorption. Compared with the literature and PPO400-GPMS, PEO500-GPMS had higher RB adsorption capacity, which indicated that the latter matrix is a highly efficient adsorbent and good candidate in the field of anion binding for applications in water treatment. The in situ UV-vis spectroscopy results and the pseudo-first order, pseudo-second order, and Morris-Weber intraparticle diffusion models allowed us to propose a three-step mechanism for RB adsorption onto PEO500-GPMS. The first step is short-range diffusion of RB molecules to the external surface of PEO500-GPMS, followed by water uptake (hydrogel behavior) by the matrix which accelerated the adsorption and diffusion process, and finally a dynamic equilibrium stage leading to the higher adsorption capacity. The thermodynamic studies provided information about the inherent energetic changes taking place in PEO500-GPMS and PPO400-GPMS during RB adsorption. The use of a distribution coefficient (D) helped to define the strength of the interaction between the hybrid matrixes and the dye in water. Comparative DSC studies showed that the presence of RB in the hybrid matrixes increased the rigidity of the polymeric backbone. We demonstrated that hybrid xerogels efficiently remove a series of anionic dyes such as Congo Red, Ponceau S, Indigo Carmine, Eosin Y, Brilliant Green and Fluorescein. The excellent water uptake, swelling behavior and the impressive anionic binding ability of PEO500-GPMS make it a highly efficient adsorbent for water purification and treatment. ; Fax: +55 16 37118961; Tel: +55 16 37118961 † Electronic supplementary information (ESI) available: In situ UV-vis additional spectra, adsorption isotherms, and thermodynamic analysis. See Scheme 2 Chemical structure of the (a) PEO500-GPMS and (b) PPO400-GPMS hybrids with the possible interaction sites: ether-type oxygen (blue), amine (red), oxygen-type alcohol (green), and (c) molecular structure of Rose Bengal dye. J. Mater. Chem. A This journal is

Humic acids (HAs) are ubiquitous macromolecules in the environment. Due to their high contents of oxygenated functional groups, they can interact with contaminants present in the natural environment and therefore influence the behavior of pollutants. However, a pH of 2 or lower is required to maintain HAs in the solid form. To increase the stability of HAs and their capacity to bind to contaminants, this work proposes the development of new hybrid materials based on alkoxysilanes and HAs for environmental applications such as dye adsorption. Three different materials with new functional groups were prepared by employing the following alkoxysilanes: tetraethyl orthosilicate, (3-aminopropyl)triethoxysilane, and N-[3-(trimethoxylsilyl)propyl]ethylenediamine. The final materials were denoted HWA, HOA, and HTA, respectively, and they were characterized by elemental analysis, diffuse reflectance Fourier-transform infrared spectroscopy (DRIFT), small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM), and N2 gas-volumetric adsorption. The point of zero charge (pzc) and stability of these materials were also determined. Their selectivity was evaluated in adsorption experiments performed with two different charged dyes in aqueous medium, namely anionic rose bengal (RB) and cationic methylene blue (MB). The elemental, DRIFT, SAXS, SEM, and textural analyses confirmed the presence of a combination of the features of HAs and alkoxysilanes. The pzc results showed that the new materials displayed different characteristics and affinities. All the materials were stable in aqueous solution up to pH 10. For MB, the percentage removal values obtained by using HWA, HOA, and HTA were 98, 85, and 67%, respectively. As for RB, the percentage removal values were 19, 18, and 44% for HWA, HOA, and HTA, respectively. These hybrid materials have potential use as adsorbents for the removal of cationic or anionic species and could be viable alternatives to remove various substances present as contaminants in natural environments.

This work reports the use of a cross-linked ureasil-PEO hybrid matrix (designated PEO800) as an efficient adsorbent to retain the emerging contaminant bisphenol A (BPA) from an aqueous medium. The in-deep experimental and theoretical results provide information about the interactions between PEO800 and BPA. The in situ UV-vis spectroscopy data and the pseudo-first order, pseudo-second order, Elovich, and Morris-Webber intraparticle diffusion models allowed us to propose a three-step mechanism for the adsorption of BPA onto PEO800. The results indicate that the pseudo-first-order kinetic model effectively describes the adsorption of BPA onto PEO800. Differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy confirmed the interaction of PEO800 with BPA, showing an alteration in the chemical environment of the polymer ether oxygen atoms present in the hybrid matrix. The molecular dynamic simulation provides further evidence that the BPA molecules interact preferentially with PEO. The amount of desorbed BPA depended on the pH and solvent used in the assays. This work provides new opportunities for using the hydrophilic ureasil-PEO matrix which has demonstrated its abilities in being a fast and easy alternative to successfully removing organic contaminants from aqueous mediums and therefore having potential applications in water remediation. Graphical abstract.

suggest that the chemical integrity of the drug is maintained upon incorporation of the drug mesoporous silica which may be favorable for controlled drug release.

Correction for 'Influence of the hydrophilic/hydrophobic nature of polyetheramines on the interaction between amine-alcohol-silicate hybrids and anionic dyes for effective water cleaning' by André L. A. Moura et al., J. Mater. Chem. A, 2015, 3, 16020-16032. Reference 26 of the above manuscript is incorrect and should include the references as shown below.