Synthesis of Mesostructured Lamellar Aluminophosphates Using Supramolecular Templates

The liquid-crystal templating approach for the synthesis of mesostructured materials was extended to aluminophosphates. A variety of lamellar AlPO 4 phases with d spacings in the nanometer range were prepared in the presence of long-chain primary and tertiary amines. A systematic study of the influence of the gel composition was carried out. AlPO 4 materials were characterized by various techniques including XRD, TEM, electron diffraction, and 27 Al, 31 P, 15 N, and 13 C NMR. The gel composition has a drastic influence on the nature of the product formed and on the coordination of aluminum and phosphorus in the final “crystalline” phase. These lamellar AlPO 4 phases were not stable under calcination conditions and the templating surfactant could not be removed by solvent extraction.