Preparation And Photoelectric Properties Of Lanthanide Metal-organic Frameworks Based On P-diphenylanthracene Polycarboxylate

The lanthanide metal-organic frameworks（Ln-MOFs）have become a research hotspot in the fields of coordination chemistry and crystal engineering due to their uniqueness of lanthanide ions and diversity of organic ligands.The construction of Ln-MOFs with novel structures and diverse functions and analyzing their applications in the fields of luminescence,electrical conductivity,magnetism,catalysis,gas adsorption and separation,and biological imaging are of great significance in emerging functional materials.In this thesis,based on crystal engineering and function-oriented,Ln-MOFs constructed based on polycarboxylic acid ligands containing p-diphenylanthracene were studied.The main results are as follows:1.Dicarboxylic acid 4,4′-（9,10-anthracenediyl）dibenzoic acid（H₂ADBA）and tetracarboxylic acid 5,5′-（9,10-anthracenediyl）di-isophthalate（H₄ADIP）as a multidentate ligand and different rare earth nitrates were solvothermally synthesized with a series of three-dimensional neutral structures Ln-MOFs 1-7 and 8-13.From the crystal structure analysis,it can be seen that 1-4 are crystallized in the trigonal space group P,and carboxylic acid group and the DMF are involved in the coordination.5-7 are crystallized in the trigonal space group P,coordinated by H₂O andacetic acid,which originates from the in-situ decomposition of DMAc.8-13 is crystallized in the monoclinic space group C₂/c.Carboxylic acid group and water are involved in the coordination,and also contains two uncoordinated carboxylic acid groups,and has a large porosity.The carboxylic acids on the two ligands lead to structural diversity through a combination of chelatingbidentate（μ₁-η¹:η¹）,bridging bidentate（syn-syn-μ₂-η¹:η¹）and chelating bidentate（syn-syn-μ₂-η¹:η²）coordination modes.2.The properties of Ln-MOFs with H₂ADBA ligand were studied.1 is Ln-MOF with magnetic refrigeration and proton conduction:-ΔS_m is 24.67 J kg^-1 K^-1 at 2 K and 7 T.3 is a bifunctional Ln-MOF with proton conduction and fluorescent properties:the proton conductivity is 2.92×10^-4 Scm^-1at 308 K and 98%RH and it can specifically recognize SA,acac,Al³⁺,Ga³⁺and Fe³⁺and is not interfered by other small organic molecules and cations.6is Ln-MOF with fluorescent properties that can selectively recognize SA,acac,Al³⁺,Ga³⁺,and Fe³⁺without interference from other small organic molecules and cations.3.A series of Ln-MOFs with H₄ADIP as the ligand were studied,9 is a bifunctional Ln-MOF with proton conduction and fluorescent properties:the proton conductivity is2.41×10^-5 S cm^-1 at 333 K and 98%RH.Fluorescence measurements show that it has fluorescence quenching effect on SA with the detection limit of 0.083μM.For acac,Al³⁺,Ga³⁺,L-Asp and L-Glu,the fluorescence enhancement effect and low detection limits were0.16μM,0.069μM,0.079μM,0.25μM and 0.23μM,respectively.It is a potential multifunctional chemo-sener.