The cross-linking density influences the physicochemical properties of cyclodextrin-based nanosponges (CD-NSs). Although the effect of the cross-linker type and content on the NSs performance has been investigated, a detailed study of the cross-linking density has never been performed. In this contribution, nine ester-bridged NSs based on β-cyclodextrin (β-CD) and different quantities of pyromellitic dianhydride (PMDA), used as a cross-linking agent in stoichiometric proportions of 2, 3, 4, 5, 6, 7, 8, 9, and 10 moles of PMDA for each mole of CD, were synthesized and characterized in terms of swelling and rheological properties. The results, from the swelling experiments, exploiting Flory–Rehner theory, and rheology, strongly showed a cross-linker content-dependent behavior. The study of cross-linking density allowed to shed light on the efficiency of the synthesis reaction methods. Overall, our study demonstrates that by varying the amount of cross-linking agent, the cross-linked structure of the NSs matrix can be controlled effectively. As PMDA βCD-NSs have emerged over the years as a highly versatile class of materials with potential applications in various fields, this study represents the first step towards a full understanding of the correlation between their structure and properties, which is a key requirement to effectively tune their synthesis reaction in view of any specific future application or industrial scale-up.

A new magnetic nanocomposite called MIL-100(Fe) @Fe3O4@AC was synthesized by the hydrothermal method as a stable adsorbent for the removal of Rhodamine B (RhB) dye from aqueous medium. In this work, in order to increase the carbon uptake capacity, magnetic carbon was first synthesized and then the Fe3O4 was used as the iron (III) supplier to synthesize MIL-100(Fe). The size of these nanocomposite is about 30–50 nm. Compared with activated charcoal (AC) and magnetic activated charcoal (Fe3O4@AC) nanoparticles, the surface area of MIL-100(Fe) @Fe3O4@AC were eminently increased while the magnetic property of this adsorbent was decreased. The surface area of AC, Fe3O4@AC, and MIL-100(Fe) @Fe3O4@AC was 121, 351, and 620 m2/g, respectively. The magnetic and thermal property, chemical structure, and morphology of the MIL-100(Fe) @Fe3O4@AC were considered by vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunner-Emmet-Teller (BET), and transmission electron microscopy (TEM) analyses. The relatively high adsorption capacity was obtained at about 769.23 mg/g compared to other adsorbents to eliminate RhB dye from the aqueous solution within 40 min. Studies of adsorption kinetics and isotherms showed that RhB adsorption conformed the Langmuir isotherm model and the pseudo second-order kinetic model. Thermodynamic amounts depicted that the RhB adsorption was spontaneous and exothermic process. In addition, the obtained nanocomposite exhibited good reusability after several cycles. All experimental results showed that MIL-100(Fe) @Fe3O4@AC could be a prospective sorbent for the treatment of dye wastewater.

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(AAM) is copyrighted and published by Elsevier. It is posted here by agreement between Elsevier and the University of Turin. Changes resulting from the publishing process-such as editing, corrections, structural formatting, and other quality control mechanismsmay not be reflected in this version of the text. The definitive version of the text was subsequently published in Microporous and Mesoporous Materials 235 (2016) 178-184. You may download, copy and otherwise use the AAM for non-commercial purposes provided that your license is limited by the following restrictions: (1) You may use this AAM for non-commercial purposes only under the terms of the CC-BY-NC-ND license. (2) The integrity of the work and identification of the author, copyright owner, and publisher must be preserved in any copy.

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We present a rapid temperature-assisted synthesis route to synthesize cyclodextrin-based metalorganic frameworks (CD-MOFs) surfactant freely in a short time. The cubic crystals of CD-MOF with an average edge length of 10-15 m, specific surface area 775 m 2 g -1 and total pore volume 0.229 cm 3 g -1 were synthesized in much shorter time rather than conventional CD-MOFs. To show the efficiency of the synthesized CF-MOF as adsorbent of gas, the uptake of CO2 at different temperature and pressure demonstrated. It is shown that the CO2 uptake increases with increasing pressure and decreasing temperature. Further microgravimetric investigation on gas adsorption at low pressures demonstrated superior gas uptake (147 mg g -1 c.a.) than previous reports. At the maximum equilibrium pressure, the uptake amounts of CO2 were found to be about the 326 and 268 mg g -1 at 303 and 323 K, respectively. The synthesized CD-MOF particles have great potential to be used in gas storage and separation applications.

Porous carbon materials have attracted great interest for their many industrial applications.

Manufactured globally on industrial scale, cyclodextrins (CD) are cyclic oligosaccharides produced by enzymatic conversion of starch. Their typical structure of truncated cone can host a wide variety of guest molecules to create inclusion complexes; indeed, we daily use CD as unseen components of food, cosmetics, textiles and pharmaceutical excipients. The synthesis of active material composites from CD resources can enable or enlarge the effective utilization of these products in the battery industry with some economical as well as environmental benefits. New and simple strategies are here presented for the synthesis of nanostructured silicon and sulfur composite materials with carbonized hyper crosslinked CD (nanosponges) that show satisfactory performance as high-capacity electrodes. For the sulfur cathode, the mesoporous carbon host limits polysulfide dissolution and shuttle effects and guarantees stable cycling performance.The embedding of silicon nanoparticles into the carbonized nanosponge allows to achieve high capacity and excellent cycling performance. Moreover, due to the high surface area of the silicon composite, the characteristics at the electrode/ electrolyte interface dominate the overall electrochemical reversibility, opening a detailed analysis on the behavior of the material in different electrolytes. We show that the use of commercial LP30 electrolyte causes a larger capacity fade, and this is associated with different solid electrolyte interface layer formation and it is also demonstrated that fluoroethylene carbonate addition can significantly increase the capacity retention and the overall performance of our nanostructured Si/C composite in both ether-based and LP30 electrolytes. As a result, an integration of the Si/C and S/C composites is proposed to achieve a complete lithiated SiÀ S cell.