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ZSM-5- and NaY-coated MCF materials as new acid catalysts for conversion of bulky molecules were prepared by the coating procedure using diluted clear zeolite gel solutions. The resulting materials have high acidity and improved steam stability as compared to that of the corresponding MCF aluminosilica. This could be due to the zeolitic nature and relative hydrophobicity of the mesopore surface.

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A new synthetic approach to generate mesostructured phosphorus-free titania is reported. Mesostructured hexagonal and lamellar titania were prepared by using the cationic surfactant C16TMA+ and soluble peroxytitanates in the presence of Na+ and TMA+, respectively. Moreover, upon hydrothermal postsynthesis, the lamellar mesophase can be converted to the hexagonal mesophase in the presence of Na+ in the liquid phase. In contrast, the lamellar structure is stable and improves under similar conditions when Na+ is replaced by TMA+.

Crystallizing walls: Following the templated solid‐state secondary crystallization of an amorphous mesoporous material the amorphous pore walls of the mesoporous precursor are partially reorganized into a crystalline material, the zeolite ZSM‐5, as indicated by the dark‐field transmission electron micrograph image shown. The bright spots correspond to the ZSM‐5 nanocrystals.

A uniform pore size with a highly ordered structure is still observed for zeolite (ZSM‐5)‐coated mesoporous aluminosilicates (ZCMesoAS) even after the coating procedure (see transmission electron micrograph). These ZCMesoAS, which are hydrothermally ultrastable and highly acidic owing to the nanocrystalline zeolitic nature of their pore wall surface, are produced from diluted clear solutions containing primary zeolite units. The novel features of ZCMesoAS open new possibilities for their use as acid catalysts.

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