Synthesis of AlPO 4-16 from fluoride-containing media in the presence of various organic templates

Abstract

Various crystallographic forms of AlPO 4-16 were prepared from F − containing media in the presence of five different organic templates. Heptamethyleneimine and 3-azabicyclo [3.2.2] nonane lead to the cubic form, whereas hexamethyleneimine and quinuclidine lead to the tetragonal form. Using cobalticinium cations, the symmetry is monoclinic. The products were characterized using several techniques such as SEM, XRD, elemental analysis, thermal analysis and solid-state NMR spectroscopy. The change in symmetry could be related to the value of the site occupancy factor of the D4R [4 6] units by the fluoride ions.