Characterized by a regular porosity in terms of pore size and pore network arrangement, ordered mesoporous solids have attracted increasing interest in the last two decades. These materials have been identified as potential candidates for several applications. However, more environmentally friendly and economical synthesis routes of mesoporous silica materials were found to be necessary in order to develop these applications on an industrial scale. Consequently, ecodesign of ordered mesoporous silica has been considerably developed with the objective of optimizing the chemistry and the processing aspects of the material synthesis. In this review, the main strategies developed with this aim are presented and discussed.

TiO2–SiO2 composites with 44 wt% of anatase exhibit a better MO degradation rate than those with fully crystallized anatase.

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As with all nanomaterials, characterization of the surface chemistry of mesoporous silicon (PSi) is crucial for the development in its diverse applications. Nuclear magnetic resonance (NMR) is one of the most powerful methods to study the chemistry of nanomaterials, but it is currently underutilized with PSi due to low signal-to-noise ratios achieved with this material which lead to very long measurement times. Here we show that endogenous radicals exist in thermally carbonized PSi and demonstrate the feasibility of solid-state dynamic nuclear polarization (DNP) NMR without addition of organic radicals. Use of DNP NMR is demonstrated to highly improve the signal-to-noise ratio while significantly reducing the measurement times. This technique opens new possibilities for the use of more advanced NMR techniques allowing the detailed characterization of complex materials such as PSi. Furthermore, the chemical structure of thermally carbonized PSi is studied by complementary techniques, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy.

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International audienceSolids composed of TiO2 nano-crystallites (10-40wt%) dispersed in an SBA-15 matrix were synthesised and used as hydrodesulfurisation (HDS) active-phase supports. Well-dispersed polymolybdate species were detected by Raman spectroscopy on all the CoMo-based oxidic precursors. Undesirable bulk CoMoO4 mixed oxide was also detected on the surface of low-TiO2-content materials, which suggests the enhancement of the Mo oxidic species dispersion as a result of the presence of TiO2. After activation under H-2/H2S, the obtained catalysts were tested in the HDS of thiophene. An optimum conversion was observed for the catalyst supported on the solid that contained 20wt% TiO2, which outperformed the homologous samples supported on TiO2 and SBA-15. This clearly highlights the beneficial effect of using such nano-TiO2-SBA-15 composite supports, in which SBA-15 confers adequate textural properties to the system, and the active phase benefits from the dispersive effect of TiO2

Albendazole (ABZ, anti-parasitic active pharmaceutical ingredient) is a crystalline low water-soluble drug, thus the dissolution rate in gastrointestinal fluids is limited. Consequently, the improvement of the water solubility and dissolution rate of ABZ implies a great challenge for a more efficient treatment of hydatidosis. In this context, SBA-15 and SBA-16 ordered mesoporous silica materials were synthetized and loaded with ABZ. X-ray diffraction, FT-IR spectroscopy, nitrogen physisorption manometry, particle size distribution and scanning electronic microscopy were used to characterize unloaded and loaded materials (ABZ/SBA-15 and ABZ/SBA-16). The loaded ABZ amount in the carriers was estimated by elemental analysis. For the loaded materials, the drug solubility and release profile were evaluated. In addition, mathematical models were compared to explain the dissolution kinetics of ABZ from mesoporous solids. ABZ was successfully loaded into the mesopores. The amorphous state of the adsorbed ABZ was confirmed by differential scanning calorimetry that resulted in a notable increment in the dissolution rate compared to crystalline ABZ. Drug release behaviors were well simulated by the Weibull model for ABZ/SBA-15 and by the Gompertz function for pure ABZ and ABZ/SBA-16. The SBA-15 carrier exhibited the highest drug loading and dissolution rate becoming a promising material to improve ABZ bioavailability.