| Summary: | 碩士 === 中原大學 === 化學研究所 === 106 === In this study, using H2TzDB (4,4''-(1,2,4,5-tetrazine-3,6-
diyl)dibenzoic acid) as an organic ligand and metal aluminum as the central
metal synthesize a porous metal organic framework(MOFs). Highly
defective Al(OH)x(solvent)y(TzDB)z-53, which was synthesized with
DEF as a solvent, with imperfect crystallinity was transformed into the
rigid and highly crystalline isomer AlTz-68 upon solvent desorption.
Topological structure from sra (square) transform to Kgm (Kagome) phase.
In order to study the structure conversion, discussions include
replacement of the solvent and the removal of the solvent. First using ether
or acetone as replacement exchanges original solution then perform
different methods of phase transformation (solvent removal). Roughly
divided into four ways(1) General dry (2) Vacuum dry (3) Solvothermal
before Vacuum dry (4) Solvothermal before General dry. To study the
structure change, with powder X-ray diffraction identification structure,
Nitrogen adsorption/desorption instrument analysis pore size distribution,
thermal gravimetric analyzer thermal stability, infrared spectrometer (IR)
to explore the changes in the functional groups.
From the above analysis, it was assumed that the structural
transformation was caused by a defect. And the solvent played a role in
inducing structural transformation. When solvent leaving caused the
movement of the ligand and eventually caused the rearrangement of the
defective MOF. Finally, it was found that after the purification have the
best crystallinity, gas adsorption, and specific surface area. Resulting in a
remarkable increase in nitrogen adsorption phase was converted to about
1050 cm3/g after conversion from about 300 cm3/g to kgm before
conversion and the surface area from 1060 m2/g to 3198 m2/g.
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