Formation of Colloidal Dispersions of Layered g-Zirconium Phosphate in Water/Acetone Mixtures

The exfoliation of zirconium phosphate with a layered structure pounds have been successfully exfoliated in an aqueous meof
the g-type is of interest from both a fundamental and a techno- dium when some short-chain alkylamines are intercalated
logical point of view. However, until now, the results reported in (2). The colloidal dispersions of layered compounds have
the literature have not been as good as those reported for a-zirconium
phosphate. It has been found that a very good exfoliation of many potential uses: preparation of high-surface-area catag-
zirconium phosphate with the formation of very stable colloidal lysts (2) , self-assembled layered structures (3) , preparation
dispersions can be obtained at temperatures higher than 557C and of pillared porous compounds by intercalation of large catfor
percentages of acetone in the range 35-80% in volume. The ionic species such as Keggin ions (4) , preparation of selfexfoliation
was attributed to the formation of an expanded acetone consistent films or materials covered with very thin pellicules
intercalated phase in which the interlayer hydrogen bonds origi- of these compounds (5), and as protonic conductors (6).
nally present in the g-ZrPO4rO2P(OH)2r2H2O are broken. By Due to the renewed interest in g-metal ( IV) phosphates
filtration of the colloidal dispersions, very compact and flexible after the elucidation of their layered structure (7, 8) and
self-consistent films can be obtained.