Luminescent And Catalytic Properties Of Lanthanide-or Zirconium-Contained MOFs

Metal Organic Frameworks(MOFs) are porous materials assembled by metal nodes and organic linkers. Due to their high surface area, large porosity, tunable structural and component, MOFs are widely applied in catalysis, gas storage, separations, and luminescence. During the past decade, post-synthesis of MOFs catch much attention of researchers. As to the modified lanthanide MOFs, researches usually focus on the influence of doping type and amount of lanthanide ions on the luminescence properties, and pay few attention on the effect of the ligand. Meanwhile, as newly-developed materials with excellent stability, post-synthesis of Zr-based MOFs is still in preliminary stage. This thesis focuses on the post-synthesis of two special MOFs materials: Lanthanide-based MOFs and Zirconium-based MOFs, and discusses the modified properties and the potential application. The main works are summarized as follow:(1) We applied the in-situ solvothermal method to synthesize a series of lanthanide-doped Indium-based MOFs: Ln-In-BTC. Thulium sensitized the luminescence of the BTC ligand and realized an abnormal lanthanide ions sensitizing ligand emitting. Through co-dope thulium, terbium, europium, we succeed in realizing white light emitting. Thulium as sensitizer sensitizes the BTC ligand emitting, while the BTC ligand, terbium, and europium act as blue, green, and red light emitter, respectively. By controlling the doping amount and doping types of lanthanide ions, we can well modified the luminescent properties.(2) The in-situ doping strategy was applied to obtain two lanthanide-doped Indium-based MOFs: Ln-In-TATB and Ln-In-BTC. The luminescent properties are detail studied and the influence of the ligand as well as the solvent polarity during the energy transfer process between terbium and europium are also discussed. While the triplet state of the ligand lies between the excited state of terbium and europium, the ligand will link the energy transfer process and improve the energy transfer efficiency. Moreover, with the solvent polarity increasing, the energy transfer efficiency increases as well.(3) Through one-step solvothermal method, PCN-700 was obtained. Then by sequential linker installation strategy, PCN-700 was turned into PCN-701. Socking the obtained samples in the H2SO4 solution with different pH value, we obtained a series of sulfonated samples which has been confirmed by IR and EDS data. The catalytic properties such as catalytic rate, conversion ratio, stability of the catalyst are detailed studied.