Magnetic Fe(2)O(3)/carbon hybrids were prepared in a two-step process. First, acetic acid vapor interacted with iron cations dispersed on the surface of a nanocasted ordered mesoporous carbon (CMK-3). In the second step, the primarily created iron acetate species underwent pyrolysis and transformed to magnetic iron oxide nanoparticles. X-ray diffraction, Fourier-transform infrared, and Raman spectroscopies were used for the chemical and structural characterization of the hybrids, while surface area measurements, thermal analysis, and transmission electron microscopy were employed to determine their physical, surface, and textural properties. These results revealed the preservation of the host carbon structure, which was homogenously and controllably loaded (up to 27 wt %) with nanosized (ca. 20 nm) iron oxides inside the mesoporous system. Mössbauer spectroscopy and magnetic measurements at low temperatures confirmed the formation of γ-Fe(2)O(3) nanoparticles exhibiting superparamagnetic behavior. The kinetic studies showed a rapid removal of Cr(VI) ions from the aqueous solutions in the presence of these magnetic mesoporous hybrids and a considerably increased adsorption capacity per unit mass of sorbent in comparison to that of pristine CMK-3 carbon. The results also indicate highly pH-dependent sorption efficiency of the hybrids, whereas their kinetics was described by a pseudo-second-order kinetic model. Taking into account the simplicity of the synthetic procedure and possibility of magnetic separation of hybrids with immobilized pollutant, the developed mesoporous nanomaterials have quite real potential for applications in water treatment technologies.

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A lightweight, oxygen-rich carbon foam was prepared and doped with Pd/Hg alloy nanoparticles. The composite revealed high H2 sorption capacity (5 wt%) at room temperature and moderate pressure (2 MPa). The results were explained on the basis of the H2 spillover mechanism using Density Functional Theory.

The synthesis of "side chain" functionalized MCM-41 inorganic-organic hybrids, through the exchange method of the template with the cationic organosiloxanes () 3 + Cl -is reported. The first two derivatives are converted to free basis by neutralization of the acidic forms with Na 2 CO 3 . After the exchange and neutralization reactions, the as received derivatives retain the hexagonal symmetry of the original MCM-41 material, whereas, due to the high loading of the pore channels of the MCM-41 silica with the organo-modifier, the final solids exhibit rather small BET surface areas (∼100 m 2 g -1 ) and microporosity. The functionalized organic moieties, covalently attached to the walls of the MCM-41 mesoporous silica, exhibit the characteristic reactions of the particular end groups, including nucleophilic substitution reactions, chelation of transition metal ions, and anion exchange behavior.

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Specular reflectance infrared and electron spin resonance spectroscopies were employed for the analysis of the sites of Li(), Cu() and Cd() cations fixed in the structure of montmorillonite from Jels ˇovy ´Potok (Slovakia) upon heating for 24 h at 300 °C. Li() cations are trapped in two different sites: in the previously vacant octahedra and in the hexagonal holes of the tetrahedral sheet. Cu() cations are fixed deep in the hexagonal holes. They substantially affect the vibration modes of Si-O bonds and they can be partially coordinated by oxygen atoms from the mineral layers and by nitrogen atoms from pyridine molecules, if present in the interlayers. The larger Cd() cations do not get so deep into the hexagonal holes as the Cu() ions and their effect on Si-O bonds is less pronounced.The authors acknowledge the financial support of NATO 89, 831. 41 F. A. Cotton and G. Wilkinson, Advanced Inorganic Chemistry,

Dropwise addition of an aqueous carboxymethyl cellulose solution to a solution of a copper or iron salt in n-butanol, leads to self-assembled, permeable millimeter sized metal-ion derivatized carboxymethyl cellulose hollow capsules of uniform dimensions and different morphologies.

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