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A simple and versatile methodology is described for tailoring sugar-functionalised gold nanoclusters (glyconanoparticles) that have 3D polyvalent carbohydrate display and globular shapes. This methodology allows the preparation of glyconanoparticles with biologically significant oligosaccharides as well as with differing carbohydrate density. Fluorescent glyconanoparticles have been also prepared for labelling cells in biological tests. The materials are water soluble, stable under physiological conditions and present an exceptional small core size. All of them have been characterised by (1)H NMR, UV and IR spectroscopy, TEM and elemental analysis. Their highly polyvalent network can mimic glycosphingolipid clustering and interactions at the plasma membrane, providing an controlled system for glycobiological studies. Furthermore, they are useful building blocks for the design of nanomaterials.

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Co⋅B‐based materials are widely used as catalysts for hydrogen generation through sodium borohydride self‐decomposition. In the mid 1990 s, the aqueous and organic chemistry involved in Co⋅B synthesis and handling was studied. Nevertheless, the exact microstructure of these catalysts has remained unsolved. Herein we present an exhaustive study which shows a new and complete microstructural view of a Co⋅B‐based material together with the chemistry of the cobalt and boron involved. By using nanoscale‐resolution microscopy and spectroscopy techniques, we have elucidated the role of boron compounds as stabilizers in a complex microstructure, which also explains its high catalytic performance and long‐term stability. The catalyst is proposed to be made up of 1–3 nm hcp Co0 nanoparticles embedded in amorphous CoxB (x=1, 2, 3), CoxOy, Co(BO2)2, and B2O3 phases alternatively or all together. All of these amorphous phases protect the nanocrystalline metallic core from growth and oxidation.

A synthetic route to building photoconducting films of TiO2 nanoparticles that display bright structural color is presented. The color arises as a result of the periodic modulation of the refractive index, which is achieved by controlling the degree of porosity of each alternate layer through the particle size distribution of the precursor suspensions. The suspensions are cast in the shape of a film by spin‐coating, which allows tailoring of the lattice parameter of the periodic multilayer, thus tuning the Bragg peak spectral position (i.e., its color) over the entire visible region. Photoelectrochemical measurements show that the Bragg mirrors are conductive and distort the photocurrent response as a result of the interplay between photon and electron transport.

An exhaustive microstructural characterization is reported for the LiBH 4-MgH 2 reactive hydride composite (RHC) system with and without the Ti-isopropoxide additive. X-ray diffraction (XRD) with Rietveld analysis, transmission electron microscopy (TEM) coupled to energy dispersive X-ray analysis (EDX), selected area electron diffraction (SAED) and electron energy loss spectroscopy (EELS) are presented in this paper as the first time for this system in all sorption steps. New data are reported regarding average crystallite and grain size, microstrain, phase formation and morphology that contribute to the understanding of the reaction mechanism and the influence of the additives on the kinetics. Microstructural effects, related to the high dispersion of titanium based additives, results in a distinct grain refinement of MgB 2 and an increase of reaction sites which causes acceleration of desorption and absorption reactions. Considerations on stability of phases under e-beam irradiation have been also reported.

A high surface area titania-zirconia mixed oxide support was prepared by the technique of precipitation from homogeneous solutions. Vanadia (12 wt %) was impregnated on TiO 2 -ZrO 2 support by using an oxalic acid solution of NH 4 VO 3 . The TiO 2 -ZrO 2 binary oxide support and the V 2 O 5 /TiO 2 -ZrO 2 catalyst were then subjected to thermal treatments from 500 to 800 °C. The influence of thermal treatments on the dispersion and stability of the catalyst was investigated by X-ray diffraction (XRD), FT infrared (FTIR), UV-vis absorption, and X-ray photoelectron spectroscopy (XPS) techniques. The characterization results suggest that the TiO 2 -ZrO 2 binary oxide support is thermally quite stable up to 800 °C. Calcination of the coprecipitated titanium-zirconium hydroxides at 500 °C result in the formation of an amorphous phase, and further heating at 600 °C converts this amorphous phase into a crystalline ZrTiO 4 compound. Impregnation of V 2 O 5 and heating of the V 2 O 5 /TiO 2 -ZrO 2 catalyst beyond 600 °C results in the formation of ZrV 2 O 7 , with the simultaneous presence of the TiO 2 rutile phase. However, the vanadia is in a highly dispersed state on the TiO 2 -ZrO 2 mixed oxide support when calcined at less than 600 °C.