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微孔金屬磷酸鹽/亞磷酸鹽與氟化物之合成、結構鑑定與性質研究
Dissertation

微孔金屬磷酸鹽/亞磷酸鹽與氟化物之合成、結構鑑定與性質研究

賴宇倫
Doctor of Philosophy (PHD), 國立清華大學, 化學系
2008

Abstract

微孔材料 金屬磷酸鹽 金屬亞磷酸鹽 microporous materials metal phsphates metal phosphites
In this research, 55 novel compounds have been synthesized by the using of organic amines as templates via the mild hydrothermal method. These compounds were all characterized by single crystal X-ray diffraction and measured physical and chemical properties. The compounds are divided into two series based on metal centers: The first series focus on uranium contained compounds including hexavalent uranium phosphates (A1 to A13), tetravalent uranium phosphates (A14 to A28) and fluorides (A29 to A34). Structural dimensionality from 0D cluster, 1D infinite chain, 2D layer and 3D bimetal open framework is discussed. Different connectivity in structure helps make clear the relationship between uranium structural chemistry and reaction variables. Moreover, organically templated uranium (IV) phosphates have never been reported not to mention one with novel structure like A14 to A28. They show strong antiferromagnetic interaction with decreasing temperature. It is worth mentioning that the chemical stability of these compounds with respect to oxidization is also dimensionality-dependent. The oxidation results also imply that the U4+ ions are more stable in the phosphate matrixes with the smaller extent of fluorination. A rule for predicting structural dimensionality can be concluded from the structure features in A14, A20, A24 and A29 to A34 and reported uranium (IV) fluorides. The second series is comprised of an extra-large microporous 26R aluminum zincphosphite, namely NTHU-5. It’s synthesized with different valance state Zn2+ and Al3+, n-butylamine (CH3CH2CH2CH2NH2) as organic template and HF, in mixed solvent (C2H5OH and H2O). Without changing the structure, trivalent metal ion, Al3+ could be completely replaced by Ga3+ or Fe3+, rendering the material from diamagnetic to ferromegnatic. Transition metal ions, such as Co2+, V3+ or Cr3+can also be separately incorporated into Zn2+, Al3+ or Ga3+ center in structure. Surprisingly, four metal ions Al3+, Cr3+, Zn2+ and Co2+ can be simultaneously inserted into the framework. The metal-incorporated positions and amounts can be clearly characterized. The NTHU-5 framework can also be induced by shorter iso-butylamine ((CH3)2CH2CH2NH2). In this series, the NTHU-5 makes breakthrough in extra-large pore size reaching 26R channel along with high product yield and various substitution of metals in framework which are rarely observed in existing system. The synthesis of zinc- (B1 and B2), gallium- (B3 to B6), vanadium gallo- phosphates (B7 and B8) and uranium germinates (B9 to B11) and their structures were categorized in appendix B. The synthesis conditions and structure information of these compounds make contribution to further research, and also be beneficial to development of novel materials in the future.

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