Studies On The Rare Earth Complexes With New Quinoline-amide Type Ligands And The Relative Luminescent Hybrid Materials

The shielding of the 4f electrons from interactions with their surroundings by the filled 5s2 and 5p6 orbitals is responsible for the interesting chemical and physical properties of the rare earth elements which be known as the treasure house of new materials. A lot of the luminescentrare earth compounds have been applied in light-conversion molecular devices and inorganic or organic light-emitting devices, because the outstanding optical properties of the rare earth cations such as long-lived, line-shaped, and position-defined luminescence. Recently, the design and assembly of functional luminescent rare earth complexes have become a challenging issue, because the organic ligand-sensitized complexes combine the outstanding optical properties of the central cations and the regulated structures of complexes with designed organic ligands. The quinoline-amide type ligands which derived from 2-substituted-8-hydroxyquinoline as the central skeleton and their rare earth complexes have been designed and synthesized. Based on the characterizations of the complexes, solid-state and solution luminescent properties of the complexes were researched. Considering the coordinatively unsaturated characters of ligands, europium complexes with the quinoline-amide type ligands might exhibit anion-responsive luminescence profiles for particular anions. The anion-selective experiments of the europium complexes with the quinoline-amide type ligands were accomplished subsequently. Meanwhile, the quinoline-amide type ligands have been immobilized in the mesoporous matrices (MCM-41 or SBA-15) and the structures of the mesoporous matrices have been determined that the highly ordered mesoporous structures were retained after the complexes covalently bonded to the channels of the matrices by the powder X-ray diffraction (PXRD), transmission electron microscope (TEM), and nitrogen (N2) adsorption/desorption. The luminescence behaviors of the complexes bonded in the mesoporous matrices were investigated and the structure-property relationships of the mesoporous hybrid materials were studied.The dissertation includes following five chapters:Chapter 1:A brief review of investigation progress of rare earth luminescent complexes and their luminescent hybrid materials were summarized.Chapter 2:Quinoline-amide type ligands L1-12 have been designed and synthesized from 2-substituted-8-hydroxyquinoline as the central skeleton and 144 rare earth complexes include rare earth nitrate and picrate with L1-12 have been synthesized and characterized. The composition and structure of the complexes can be characterized by means of elementary analysis, molar conductance, IR and single-crystal X-ray analysis. The results determined that the ligands wrap around the metal ion with its coordination groups and the structure of the complexes were not influenced obviously by the anion.Chapter 3:Photoluminescence studies of europium complexes show that the quinoline skeletons have good sensitive function to europium ions. The results of the triplet state energy levels T1 of the ligands L1-12 indicated that these ligands are suitable sensitizers for europium. Considering the coordinatively unsaturated characters of the quinoline-amide type ligands, europium complexes with ligands L1-12 might exhibit anion-responsive luminescence profiles for particular anions, because the stoichiomatry, geometry, and structure of the ternary "ligand-lanthanide-anion" complex are often alerted by the additional coordination from external anion. The Eu3+ complexes with ligands L1-12 exhibited the similar anion-response luminescence behaviors which the luminescence increased upon addition of both Cl- and NO3-.Chapter 4:Novel organic-inorganic luminescent mesoporous hybrid materials were assembled through the coordination reaction between europium nitrate with chelated quinoline-amide type ligands immobilized in the mesoporous materials (MCM-41 and SBA-15). The mesoporous hybrid materials were characterized by elemental analysis, Fourier transform infrared spectra, powder X-ray diffraction (PXRD), transmission electron microscope (TEM), and nitrogen (N2) adsorption/desorption. The results demonstrated that the highly ordered mesoporous structures were retained after the complexes covalently bonded to the channels of the matrices. The SBA-15-type hybrid materials, which pore size is twice of MCM-41, display more efficient emission due to the spatial confinement of the nanochannel of mesoporous matrix. This deduction may be validated deeply by the fact that the influences are more obvious for the complexes including rigid end group ligands. In addition, the Eu3+ complexes coordinated with the ligands containing rigid end groups in MCM-41 matrices exhibit better photoluminescence stability upon exposure to ultraviolet light.The ligands involved in the dissertation are listed as follow: L1:2-(2-(1,3-dioxolan-2-yl)quinolin-8-yloxy)-N-phenylacetamide L2:2-(2-(1,3-dioxolan-2-yl)quinolin-8-yloxy)-N-benzylacetamide L3:2-(2-(1,3-dioxolan-2-yl)quinolin-8-yloxy)-N,N-diphenylacetamide L4:2-(2-(1,3-dioxolan-2-yl)quinolin-8-yloxy)-N,N-diisopropylacetamide L5:2-(2-(1,3-dioxolan-2-yl)quinolin-8-yloxy)-1-(piperidin-1-yl)ethanone L6:2-(2-(1,3-dioxolan-2-yl)quinolin-8-yloxy)-1-morpholinoethanone L7:2-(2-(4-methyl-1,3-dioxolan-2-yl)quinolin-8-yloxy)-N-phenylacetamide L8:2-(2-(4-methyl-1,3-dioxolan-2-yl)quinolin-8-yloxy)-N-benzylacetamide L9:2-(2-(4-methyl-1,3-dioxolan-2-yl)quinolin-8-yloxy)-N,N-diphenylacetamide L10:2-(2-(4-methyl-1,3-dioxolan-2-yl)quinolin-8-yloxy)-N,N-diisopropylacetamide L11:2-(2-(4-methyl-1,3-dioxolan-2-yl)quinolin-8-yloxy)-1-(piperidin-1-yl)ethanone L12:2-(2-(4-methyl-1,3-dioxolan-2-yl)quinolin-8-yloxy)-1-morpholinoethanone...