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Ibuprofen molecules have been encapsulated in mesoporous MCM-41 type-silica functionalised or not by amino groups. They have been characterised by 13C and 1H solid state NMR spectroscopy. The 13C MAS single pulse or cross polarization NMR spectra, as well as the 1H MAS NMR spectra demonstrate an extremely high mobility of the ibuprofen molecules when the matrix is not functionalised. On the contrary, when the silica matrix is functionalized by amino groups, the 13C NMR response shows less mobility suggesting the existence of interactions between the amino groups and the carboxylic groups. Benzoic acid as well as benzamide have also been encapsulated and their NMR responses compared to that of ibuprofen.

Vanadium oxide nanotubes (VO x -NT) have been prepared by mixing hexadecylamine with V2O5·nH2O gels. This procedure was followed by an hydrothermal treatment (150–180°C, 2–7 days) which leads to a large quantity of VO x -NT. SEM and XRD analysis have been used to optimize the temperature and reaction time required for production of VO x -Nt and morphology of the nanotubes investigated by TEM.

Polyvinyl alcohol/Poly-aniline/Vanadium Oxide nanocomposite-based macroscopic fibers have been generated by using a redox reaction addressed while performing an extrusion shaping process. The resulting composites have been thoroughly characterized via a large set of techniques such as SEM, SAXS, XRD and FTIR, in order to determine aniline effects over final materials' structures and properties. Thus, the perturbation of the preferential orientation of the V2O5 nano-ribbons toward the fiber main axis, induced by aniline Red-ox intercalation, has been observed. Also, the partial reduction of V5+ species to V4+ ones, due to the strongly oxidizing character of the first ones toward aniline, has been revealed by Electron Spin Resonance (ESR). Moreover, these fibers are able to detect 5 ppm of ethanol within 3-5 seconds at 42 °C, and possess a toughness of 12 J.g-1.

Vanadium oxide-collagen hybrid nanocomposites were prepared by adding a V2O5 sol to a dilute collagen solution. 51V MAS NMR spectroscopy shows that the inorganic phase is composed of the decavanadate [H2V10O28]4− polyanion and V2O5 ribbon-like particles. The broadening of the 51V signals and the absence of Bragg peaks in the XRD pattern suggest a strong disorder concerning the organization of the V2O5 particles and of the decavanadate species in the composites. Analogous hybrid nanocomposites were obtained with a solution that contains only the decavanadate species, showing that the cohesion in the hydrid material results mainly from electrostatic interactions between decavanadate [H2V10O28]4− polyanions and positively-charged collagen helices.

A complete solid state NMR characterization of the vanadium oxides Cs[V3O8] and Cs2[V6O16].0.7H2O is proposed. We used 51V and 133Cs MAS NMR to investigate the local environment of cesium and vanadium nuclei and 2D 1H- 133Cs CP MAS HETCOR experiments to explore the connectivities between cesium ions and water molecules in the interlamellar space.

Chemistry of shapes appears as a strong interdisciplinary field of research that encompasses both the area of soft matter, physical-chemistry and soft chemistry. In this general context, hierarchical inorganic macrocellular monoliths have been obtained using air-liquid foams as a macroscopic pattern while lyotropic mesophases are employed to create porosity at the mesoscale. At the macroscopic length scale, both cell sizes and shapes as well as the Plateau borders thickness and topologies can be designed with a strong degree of control. Some examples with different inorganic network as TiO2 and V2O5 are depicted with specific characterizations.

Various cations (Li+, Na+, K+, NH4+, Cs+, Mg2+, Ca2+, Ba2+) were introduced during the formation of a V2O5. nH2O gel. Cation intercalated Xy V2O5. nH2O (y = 0.3 for X = Li+, Na+, K+, NH4+ or y = 0.15 for Mg2+, Ca2+, Ba2+) were first obtained at room temperature but some of them evolve upon ageing into a new phase: XV3O8. nH2O for X = Na+, K+, NH4+ and Cs+ or XV6O16. nH2O for X = Mg2+, Ca2+, Ba2+. All the vanadium oxide phases were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and infrared spectroscopy (IR); the supernatant solutions were analysed by 51V NMR spectroscopy. These vanadium oxide phases exhibit a layered structure with cations and water molecules intercalated within the interlayer space. The formation of the different phases depends mainly on the pH of the supernatant solution and on the nature of the cation.

The synthesis of vanadium oxide nanotubes containing phosphorus (VPOx-NT) is described. A mixture of V2O5.nH2O gels, phosphoric acid and hexadecylamine was heated under hydrothermal conditions at 180°C for 7 days. The VPOx nanotubes were characterized by X-ray diffraction, scanning and transmission electron microscopy, 51V and 31P solid state NMR. In-situ experiments were performed in order to get a better understanding of the mechanism of these nanotubes formation.

Mesoporous silica materials have been studied for the time-dependent delivery of bioactive agents. It has already been shown that ibuprofen molecules can be encapsulated with loading as high as 30 wt% in MCM-41 silica, functionalized or not by amino groups. Interactions between the guest molecules and the host matrix have been investigated by 1H, 29Si and 13C solid state NMR spectroscopy. These experiments demonstrate an extremely high mobility of the ibuprofen molecules when the matrix is not functionalized, despite of the presence of a carboxylic function on the ibuprofen molecules. On the contrary, when the silica matrix is functionalized by amino groups, the 13C NMR response shows a strong restriction in mobility suggesting the existence of interactions between the amino groups and the carboxylic groups.

Tetramethylammonium (TMA) polyoxovanadates have been precipitated from aqueous solutions aroundpH 7. Decavanadate clusters (TMA)4[H2V10O28]•4H2O are formed at room temperature whereas a layered (TMA)[V4O10] mixed valence compound is formed under hydrothermal conditions.51V NMR spectra recorded on the solution at different temperatures show that upon heating decavanadate clusters are progressively transformed into cyclic [V4O12]4−metavanadates. This suggests that the mixed valence polyoxovanadates are formed via the ring opening polymerization of metavanadate precursors.

The non hydrolytic synthesis of several titanium oxo-alkoxo clusters Ti3O(OPri) 8(OR)2, Ti11O13(OPri)18, Ti7O4(OEt)20 and Ti16O16(OEt )32 have been performed via thermolysis of different titanium alkoxides (Ti(OEt)4, Ti(OPri)4). The structures of these clusters were mainly determined by X-ray diffraction, 17O NMR and 13 C NMR.

Porous inorganic solids can be synthesized in complex forms1,2, and here we describe a simple method to create an ultralight, macroporous, crystalline vanadium oxide foam by bubbling oxygen gas produced in situ through a viscous vanadium oxide gel. This foaming process could be extended to other metal oxides.