A Layered Titanium Phosphate Ti2O3(H2PO4)2•2H2O with Rectangular Morphology: Synthesis, Structure, and Cysteamine Intercalation

Layered titanium phosphate (TiP) composed of rectangular-shaped lamellae was synthesized from titanium isopropoxide and orthophosphoric acid. The as-prepared TiP was refluxed in a 2-propanol/water mixture at similar to 363 K for periods up to 144 h. The bulk and surface properties of the lamellar material with novel morphology were studied. The structural investigations and elemental analysis identified TiP as Ti2O3(H2PO4)(2)center dot 2H(2)O. The reactions of the TiP samples with cysteamine (CEA) in aqueous suspensions afforded TiP/CEA intercalation complexes. X-ray measurements on these complexes revealed CEA monolayers incorporated between the TiP lamellae, increasing the original basal spacing from 1.00 nm to 1.43 nm. The enthalpy change of the intercalation reaction was measured by isothermal titration calorimetry. The amount of CEA adsorbed was determined, and differential adsorption enthalpy was calculated via the mass balance.