| Metal-organic frameworks(MOFs),also named as porous coordination polymers(PCPs),have drawn widely attention and develop fast in chemistry and materials science during the last two decades.As one porous crystalline materials,MOFs consist of ions/clusters and organic linkers which mostly possess carboxylates,N-donor groups,or phosphonates.Now,more than 20 000 MOFs have been reported,which can be attributed to the abundant metal ions and organic linkers.Apart from their diverse compositions,MOFs have uniformpore sizes,high pore volume and surface areas,which promote their use in gas sorption and separation,heterogeneous catalysis and drug delivery.However,traditional bulk MOFs cannot always fulfill these applications,which attracts miniaturized MOFs.Compared with traditional large MOFs,micro and nano-scale MOFs usually possess specific morphology and size,higher specific surface area and pore volume,as well as better dispersibility in water or organic solvents.Therefore,miniaturizing MOFs to micro or nanometer scale can improve their applicability in gas adsorption,catalysis,etc.Additionally,micro and nano-scale MOFs always lead to smaller thickness and shorter molecules diffusion distance in MOFs pores,which can make great contribute to improve the transmission dynamics of MOFs.In addition,MOFs serving as host matrix to develop active guest molecules is another way to expand their applications.Chapter 1:stating briefly the definition,synthesis,and applications of MOFs.Meanwhile,explaining the advantages of micro-nano MOFs as well as the synthetic method of MNPs@MOFs.Chapter 2:synthesizing a novel three-dimensional(3D)microporous MOF-Co which was further microminiaturized to submicron-scale(SMOF-Co)with thickness of ca.450 nm and length of ca.2.5 μm.SMOF-Co was then used as adsorbent of micro solid phase extraction(μ-SPE)to determination the trace hydroxyl polycyclic aromatic hydrocarbons(OH-PAHs)in complex human urine with satisfactory sensitivity and good precision by online-coupled to liquid chromatography-mass spectrometry(LC-MS),which can be attributed to the π-π and H-O…H between SMOF-Co and OH-PAHs,as well as the high specific area of SMOF-Co.This represents the first example of a mixed-ligand-based MOF applied as an efficient sorbent of μ-SPE.Chapter 3:A novel three-dimensional(3D)microporous MOF-Ni which possesses the same structure with MOF-Co was obtained using 5,4-PMIA and TPOM as organic ligands and Ni(Ⅱ)as metal nodes.Moreover,the nanostructure of MOF-Ni was achieved by a bottom-up synthesis route via the facile surfactant-assisted method.In principle,the available well-dispersed micropores and functional oxygen sites within NMOF-Ni are desirable for confining and stabilizing Au NPs with the size of around 1 nm.As expected,ultra-small Au NPs embedded within 2D NMOF-Ni nanosheets has been successfully fabricated via solution impregnation,which turns out to be the first case of mixed-ligand-based 2D MOF nanosheets for Au NPs deposition,to the best of our knowledge.Noably,the resulting Au NPs immobilized 2D MOF nanosheets exhibit excellent catalytic performance and good size selectivity.Chapter 4:By using adsorption/reduction solution impregnation method,Pt@NMOF-Ni was synthesized.Meanwhile,NMOF-Ni nanoparticles,Au@NMOF-Ni,and Pt@NMOF-Ni were used as sacrificial templates to develop MOF deriving heterozygous nanometer materials(NiCN,AuNiCN,PtNiCN)in high temperature.In addition,the size of Au nanoparticles in Au@NMOF-Ni after high temperature calcinations were studied,meanwhile,the effect of calcination temperature and calcination atmosphere on Pt nanoparticle size in Pt@NMOF-Ni was investigated.Chapter 5:summarizing the innovation and research finding of this paper,simultaneously,outlooking the new performance of micro-nano MOFs and MNPs@MOFs composite,as well as MOFs deriving materials. |
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