Layered Aluminophosphates: Intercalation And Synthesis Studies

Porous materials constitute an important class of materials in the field ofmaterials science. Their unique pore architectures have made them popular in awide range of applications in catalysis, adsorption, separation and host-guestassemblies. Microporous aluminophosphates are an important class ofmicroporous materials, which have potential applications as their analogouealuminosilicate zeolites. In recent years, using a solvothermal technique, a largenumbe of new aluminophosphates with different Al/P ratios, and various structuraldimensionalities with 0-D clusters, 1-D chains, 2-D layers, and 3-Dopen-frameworks have been successfully synthesized by our group and others. Thefamily of aluminophosphates exhibits rich structural chemistry, among which themembers of 2D layered materials show diverse stoichiometries, sheet structuresand sheet stacking sequences. All of these layered aluminophosphates have theterminal P=O or P-OH groups, which imply that they have the ability to formhigher dimensional structures. These layered compounds will be a class of usefulmaterials if they have capability to accommodate functional organic ions andmolecules to form pillared compounds.In this thesis, we present the investigation on the intercalation chemistry, aswell as synthesis of these materials.Layered aluminophosphate [Al2P3O10(OH)2][C6NH8] with 4,6 net networkcan be delaminated successfully and reassembled into new layered compounds inwater/ethanol and water/methanol solutions with favorable dielectric constant. Thebasal space of the intercalation products with n-alkylamines increase with anincrease of the number of carbon atoms in the n-alkyl chain, and a linearrelationship between the basal space d and the number of carbon atom nc in then-alkylamines, can be observed, as expressed with d = 0.18 nc + 1.00. the alkylchains are arranged as bilayers in the interlayer region with a tilted angle of 45.13°.However, the breaking of the Al–O–P bonds in the layers during the delaminatingprocess resulted in the degradation of the crystalline layers. A more rigid layered aluminophosphate [Al3P4O16H][N2C3H5] with double-6net can also can be delaminated and reassembled into new layered compounds inwater/ethanol and water/methanol solutions. The basal space of the intercalationproducts with n-alkylamines increase with an increase of the number of carbonatoms in the n-alkyl chain, and a linear relationship between the basal space d andthe number of carbon atom nc in the n-alkylamines, can be observed, as expressedwith d = 0.153 nc + 1.07. the alkyl chains are arranged as bilayers in the interlayerregion with a tilted angle of 37.04°. During the delaminating process, the layershave been destroyed. The n-alkylamines can be successfully intercalated into the layeredaliminuphosphate [Al8P10O40H2][(C2H5)2NH2]4·[H2O]2.5 in methanol solvent toform intercalation compounds. The inorganic sheet structure can be kept intactafter the intercalation reaction. The interlayer distance of Mu-4-Ln increase withan increase of the number of carbon atoms in the n-alkyl chain, and n-alkylaminesexhibit a bilayer arrangement in the interlayer space with the tilt angle of 33.4°.Furthermore, the mesostructured lamellar aluminophosphates show reversibleintercalation and de-intercalation behavior as well as selectively intercalation ofn-alkylamines with longer n-alkyl chain. The interesting feature of this approachto the synthesis of mesostructured aluminophosphate phases is that it is possible toobtain a mesolamellar phase having the same Al-O-P connectivity as the startingphase. Several layered aluminophosphates with different stoichiometries and sheetstructures can form n-alkylamines intercalation compounds with intact layeredstructure. After careful investigation of these structural features, we find that thecompound with bigger interlayer distance can accommodate other moleculeseasier. We also successfully synthesized three layered aluminophosphate compoundswith various stoichiometries and structural dimensionalities.[Al6P8O32][(C2H5)2NHCH2CH2NH3]2[C2H5NH2CH2CH2NH2C2H5] is a newlayered aluminophosphate with an Al/P ratio of 3/4. Its structure contains4×6×8-net macroanionic sheets stacked in an ABAB sequence. Two kinds oforganic cations, diprotonnated N,N-diethylethylenediamine and its rearrangedproduct N,N'-diethylethylenediamine locate between the adjacent layers. Theirco-templating role in the formation of this Compound was also studied in terms ofhost-guest interaction. [Al2P3O12H][CH3CH (NH3)CH2CH3]2 is a new layeredaluminophosphate with an Al/P ratio of 2/3. Its structure contains 4×6×8-netmacroanionic sheets stacked in an AAAA sequence. We also study the nonbondinginteraction energies between the inorganic layers with [Al2P3O12H]2-stoichiometryand the organic amines. [H3N(CH2)4NH3]2 [Al4P6O20(OH)4(C2O4)] [H2O]4 is a new...