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Abstract: We present a general review on the synthesis of mesoporous silica obtained with nonionic surfactants and bloc-copolymers as templates. This silica, referred as MSU silica, was obtained by a two-step process that led to the formation of stable hybrid micelles after a first stage of assembling between silica and surfactants, followed by the fluoride-catalyzed condensation of silica. This process allows some unique features: the final pore size can be adjusted with some synthesis parameters such as temperature or amount of catalyst, the particle shape is spherical and in the micrometric range, different shapes and nanostructures can be achieved, including hexagonal-like frameworks. Finally, we demonstrate how an accurate control of the synthesis itself may allow us to adapt this synthesis for applications dedicated to separation processes, including liquid filtration of HPLC chromatography. To cite this article: É. Prouzet, C. Boissière, C. R. Chimie 8 (2005). [Copyright &y& Elsevier]

Abstract: Solid-state NMR methods based on dipolar and J-derived experiments such as CP, MAS-J-HMQC and MAS-J-INEPT MAS have been developed in the frame of the {31P,29Si} spin pair. The potential of these techniques has been demonstrated using model compounds including crystalline silicophosphate phases (Si5O(PO4)6 and various SiP2O7 polymorphs). Spatial interactions as well as through-bond connectivities were established. Evaluation of isotropic 2 J P–O–Si coupling constants has been established by careful analysis of the HMQC and INEPT build-up curves under fast MAS. The efficiency of the 31P→ 29Si CP MAS experiment for the detailed characterization of Si–O–P mesoporous materials (at low temperature) was demonstrated. The incorporation of P atoms in the silica network has been proved unambiguously. Such materials could be appropriate for biocompatibility purposes. [Copyright &y& Elsevier]