Imogolite-like nanotubes have been synthesised in which SiCH(3) groups have been introduced in place of the SiOH groups that naturally occur at the inner surface of imogolite, an alumino-silicate with formula (OH)(3)Al(2)O(3)SiOH, forming nanotubes with inner and outer diameter of 1.0 and 2.0 nm, respectively. The new nanotubular material, composition (OH)(3)Al(2)O(3)SiCH(3), has both larger pores and higher specific surface area than unmodified imogolite: it forms as hollow cylinders 3.0 nm wide and several microns long, with a specific surface area of ca. 800 m(2) g(-1) and intriguing surface properties, due to hydrophobic groups inside the nanotubes and hydrophilic Al(OH)Al groups at their outer surface. Adsorption of methane at 30 °C has been studied in the pressure range between 5 and 35 bar on both the new material and unmodified imogolite: it resulted that the new material adsorption capacity is about 2.5 times larger than that of imogolite, in agreement with both its larger pore volume and the presence of a methylated surface. On account of these properties and of its novelty, the studied material has several potential technical applications, e.g. in the fields of gas chromatography and gas separation.

A hybrid aerogel, composed of MoS sheets of 1T (distorted octahedral) and 2H (trigonal prismatic) phases, finely mixed with few layers of reduced graphene oxide (rGO) and obtained by means of a facile environment-friendly hydrothermal cosynthesis, is proposed as electrode material for supercapacitors. By electrochemical characterizations in three- and two-electrode configurations and symmetric planar devices, unique results have been obtained, with specific capacitance values up to 416 F g and a highly stable capacitance behavior over 50000 charge-discharge cycles. The in-depth morphological and structural characterizations through field emission scanning electron microscopy, Raman, X-ray photoelectron spectroscopy, X-ray diffraction, Brunauer-Emmett-Teller, and transmission electron microscopy analysis provides the proofs of the unique assembly of such 3D structured matrix. The unpacked MoS structure exhibits an excellent distribution of 1T and 2H phase sheets that are highly exposed to interaction with the electrolyte, and so available for surface/near-surface redox reactions, notwithstanding the quite low overall content of MoS embedded in the reduced graphene oxide (rGO) matrix. A comparison with other "more conventional" hybrid rGO-MoX electrochemically active materials, synthesized in the same conditions, is provided to support the outstanding behavior of the cosynthesized rGO-MoS.

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Pure and Fe-doped CeO2 nanoparticles obtained by microwave assisted combustion synthesis: Physico-chemical properties ruling their catalytic activity towards CO oxidation and soot combustion / SAHOO, TAPAS RANJAN;

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Adsorption of CO 2 at subatmospheric pressure at temperatures about ambient has been studied on three materials: (i) imogolite (IMO, chemical formula (OH) 3 Al 2 O 3 SiOH)) a hydrated alumino-silicate occurring as nanotubes (NTs) with bridged AlOHAl groups at the outer surface and Si−OH groups at the inner surface; (ii) an imogolite-like material (Me-IMO, chemical formula (OH) 3 Al 2 O 3 SiCH 3 ) with Si-CH 3 groups replacing Si−OH at NTs inner surface; (iii) a material (Me-IMO-NH 2 ) obtained by grafting 3-aminopropylsilane at the outer surface of Me-IMO. All materials, being in the form of NTs, exhibit rather high specific surface area values (355−665 m 2 g −1 ) and are accessible to CO 2 molecules. Infrared spectroscopy shows that carbon dioxide may interact in a variety of ways. At the inner surface of IMO, linear molecular species are reversibly formed by interaction with silanols, whereas at the outer surface carbonate-like species are given rise with partial reversible character. With Me-IMO, no interaction takes place at the inner surface: linear species are formed in the intertube nanopores as well as carbonate species as in the case of IMO. Finally, with Me-IMO-NH 2 , all species present in Me-IMO are found, as well as reversible carbamate species arising from the reaction with amino groups. Optical isotherms concerning molecular adsorption have Langmuir character, whereas those for the reversible formation of carbonates/carbamates are of Henry-type. Volumetric isotherms are interpreted as due to two independent families of adsorption sites, respectively Langmuir and Henry: comparison between optical isotherms (measured at ca. 33 °C) and volumetric isotherms (measured at 0 °C) allows a semiquantitative estimate of the adsorption enthalpy for molecular species, corresponding to ca. −20 kJ mol −1 , for linear species reversibly formed by interaction with inner silanols in IMO, and to a relatively high adsorption enthalpy for molecular species formed in the larger intertube nanopores of Me-IMO (ca. −32 kJ mol −1 ).