| As a new type of multifunctional porous materials,metal–organic frameworks?MOFs?with fine-tuning of pore surface,well-defined open channels and tunable pore sizes,have attracted fairly extensive attention in recent years.MOFs exhibit potential applications in gas storage and/or separation,magnetism,fluorescent sensing,proton conduction,drug delivery and so on.After continuous exploration for many years,the structures and properties of metal-organic frameworks have been studied deeply.Therefore,developing metal-organic frameworks with new features will be a huge challenge.In this thesis,three multi-aromatic hydrocarbon carboxylate ligands based on pentiptycene?H4L1,H2L2 and H2L3?have been designed and synthesized.Among them,H4L1and H2L2 are rigid ligands and H2L3 is a flexible ligand.Using these three ligands and metal ions,five metal-organic frameworks?UPC-21,UPC-28,UPC-29-1,UPC-29-2 and UPC-29-3?have been successfully constructed under different conditions and structurally characterized by single-crystal X-ray diffraction analyses,powder X-ray diffraction?PXRD?,thermogravimetric analyses?TGA?and elemental analyses.Besides,these five MOFs have been applied in gas adsorption and separation,fluorescent sensing,dyes adsorption,oil/water separation.The main contents are as follows:?1?A new metal-organic framework?UPC-21?has been synthesized by using H4L1 and Cu2+.The structure is a 3D porous framework with binuclear Cu-paddlewheel SBUs and BET surface area of 1117.0 m2·g-1.UPC-21 shows good property of fluorescence emission and effective detection of NACs,such as 4-NP,1,4-DNB and NB with the calculated quenching constants,Ksv,being 3.097×106,1.406×106 and 4.420×105.This is the first porous Cu???MOF that exhibits fluorescent detection of NACs with high sensitivities.?2?Large and high-crystallinity crystals of UPC-21 could be obtained through a developed“diauxic growth”strategy with BET surface area from 1117.0 m2·g-1 increasing to1725.1 m2·g-1.UPC-21 can take up acetylene up to 196.5 cm3 g-1 at 273 K and 1 bar.Besides,UPC-21 exhibits high hydrophobicity with the water contact angle of 145±1?and superoleophilicity with the oil contact angle of 0?.Strikingly,oil/water separation measurements reveal that UPC-21 can efficiently separate toluene/water,hexane/water,gasoline/water,naphtha/water with the separation efficiency being above 99.0%.This is the first work for metal-organic frameworks applied in oil/water separation.?3?A new metal-organic framework?UPC-28?has been synthesized by using H2L2 and Mg2+.The structure is a 2D porous layer-stacking framework with trinuclear Mg SBUs and BET surface area of 648.9 m2·g-1.UPC-28 can take up 196.5 cm3 g-11 H2 at 273K and 1bar.It is noteworthy that UPC-28 exhibits remarkable water-stability and performs efficient detection of Ba2+(Ksv,8.97 x 105)and adsorption of cationic dye molecules from water.?4?A new metal-organic framework?UPC-29-1?has been synthesized by using H2L3and Cu2+.The structure is a 2D layer-stacking framework with binuclear Cu-paddlewheel SBUs.There are two coordinated DMF in the axial direction of the SBU.However,the two DMF can be gradually replaced by H2O and two new metal-organic frameworks,UPC-29-2?one H2O and one DMF?and UPC-29-3?two DMF?can be obtained through single-crystal-to-single-crystal transformation.UPC-29-1 is composed of hydrophilic group?Cu-paddlewheel SBUs?and oleophilic group?pentiptycene-based frameworks?.When UPC-29-1 in the loose state for oil/water separation,UPC-29-1 allows water to be permeate but oil to be resisted.However,when UPC-29-1 in the pressed pellet form for oil/water separation,the oil can through the crystals and the water can not. |
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