| Layered inorganic compounds have been interesting to physical scientists, chemists and materials scientists for many years because of their unique structural properties and important applications such as in intercalation reactions and ion-exchange processes. The remarkable ion-exchangeability and or the potential ability of exfoliation to all these coumpounds have been considered as a key factor in synthesizing insert-compounds. There are two subsystems with different unit cell dimensions in the misfit-layered compounds. The misfit-layered compounds are very interesting because of their unusual structures as well as their properties, and have great potential applications in the fields of the electronic materials, the optic materials, the electrical materials, the magnetic materials, the catalytic materials and so on.KCa2Nb3O10,KTiNbO5 are the layered compounds with perovskite structure, K0.81Li0.27Ti1.73O4 is a typical semiconductor material. In this thesis by using KCa2Nb3O10,KTiNbO5 and K0.81Li0.27Ti1.73O4 as precursors a series of layered insert compounds have been synthesized. The structures, compositions and properties of these compounds have been studied by XRD, IR, TG-DTA, SEM, TEM, ICP and so on.We have attempted to synthesize compounds built with two sublattices using KCa2Nb3O10 as the precursor by hydrothermal synthesis. But because of the higher charge density of the sheets, the exfoliation of the layered sheets can not be sufficient. So we could not obtain the pure phase. Magnesium titanium niobium oxide (MTiNbO),Mg·(TiNbO5)2.3·H0.3·4.2H2O, has been hydrothermally synthesized by using KTiNbO5 as a precursor. MTiNbO is a layered compound and it will lose all of the water at 500℃. Nickel titanium niobium oxide (NTiNbO), Ni·(TiNbO5)2.2·H0.2·8.16H2O, has been hydrothermally synthesized by using KTiNbO5 as a precursor. NTiNbO is a layered compound and will lose the water when it is calcined at 450℃.The misfit-layered magnesium titanium oxide (MTO), [Mg0.7(OH)0.32 (H2O)1.08]Ti1.73O4·1.95H2O, has been hydrothermally synthesized. There are two sublattices in MTO, i.e. the pseudo-hexagonal sublattice of Mg(OH)2 and the orthorhombic sublattice of TiO2, and the two sublattices are incommensurate along the ab plane. The lattice parameters are as follows: a1=0.626nm and c1 =1.119nm for Mg(OH)2 pseudo-hexagonal sublattice, and a2=0.337nm, b2=0.267nm, c2=1.119nm for TiO2 orthorhombic sublattice. |
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