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Abstract: The present review outlines the research work realized during last the 10 years in our laboratory in the field of the conception of new nanostructured porous materials, from mesoporous silicas and metal oxides to hierarchical meso–macroporous compounds with various compositions (single and binary metal oxides and aluminosilicates, aluminophosphates and silicoaluminophosphates). An accent was especially made on the evolution in the development of new synthesis strategies for the introduction of a hierarchy in one solid body with and without surfactant molecules. To cite this article: B.-L. Su and al, C. R. Chimie 8 (2005). [Copyright &y& Elsevier]

Abstract: The H4PMo11VO40 heteropolyacid (HPA) was supported at 30wt.% by the dry impregnation method on HMS, CMI-1 and SBA-15 mesoporous materials. The state of the HPA and those of the supports were examined by nitrogen physisorption, X-ray diffraction, (DR) FT–IR and X-ray photoelectron spectroscopies, thermal analysis (TG–ATD) and scanning electron microscopy (SEM). The effect of support on the catalytic behavior of H4PMo11VO40 was studied in the propene oxidation at 350°C. It was shown that the presence of H4PMo11VO40, modifies the textural properties of mesoporous materials (decrease of surface area) without destroying their structure. The interaction support–heteropolyacid leads to the formation of (SiOH2+)(H3PMo11VO40 −) surface species more stable than H4PMo11VO40 species and that appear to be the active sites in the propene oxidation. [Copyright &y& Elsevier]

Abstract: Catalytic performances of nanostructured mesoporous TiO2–ZrO2 mixed oxides impregnated by Pd and/or Au were studied in toluene total oxidation in a fixed bed microreactor and with “operando” DRIFT. Mesoporous TiO2–ZrO2 mixed oxides with various Ti:Zr mole ratio of 80/20, 50/50 and 20/80, high surface areas were synthesised using a mixture of zirconium propoxide and titanium isoporopoxide as Zr and Ti sources and also CTMABr as surfactant. The new supports are impregnated by 0.5 or 1.5wt% of palladium and 1wt% of gold using impregnation and Deposition–Precipitation methods. The catalytic activity for the nanostructured mesoporous TiO2−–ZrO2 mixed oxides varies depending on the molar ratio of Ti:Zr and also for all series of the studied catalysts impregnated by Pd and/or Au, when the gold is loaded firstly the activity in toluene complete oxidation is higher than when Pd was deposited firstly (PdAu/TZ>1.5Pd/TZ>AuPd/TZ>Pd/TZ>Au/TZ>TZ). The highest activity of PdAu/TZ (80/20) can be related to the higher acid sites density of the support and also to the presence of a synergetic effect between palladium and gold. “Operando” DRIFT allowed following the VOCs oxidation but also suggesting an interaction between the adsorbed molecule and the catalyst which decreases when the activity for oxidation reaction increases. [Copyright &y& Elsevier]