| In this thesis,series of white light-emitting hybrid materials which can be used as the emitting layers of WPLEDs,were synthesized by pre-coordination of small-molecule lanthanide complexes to post-polymerization or physical doping into polymerix matrix.Firstly,three series of small molecule monomers were obtained:Schiff-base-Zn monomer Zn(L1)(4vp)(H2L1 = N,N'-phenylene-bis-(3,5-di-tert-butylsalicylimine);4vp = 4-vinylpyridine)containing a functional C=C bond;lanthanide complexes Ln(Tfac)3(5-Br-2,2'-bpy)(5-bromodipyridine)(Ln = La,1;Ln = Eu,2;Ln = Tb,3;Ln = Gd,4)with the neutral ligand 5-Br-2,2'-bpy and trifluoroacetylacetone(HTfac);the lanthanide complex Ln(Tfac)3(4-vp-2,2'-bpy)(Ln = La,5;Ln = Eu,6;Ln = Tb,7;Ln = Gd,8),which based on tri-(f3-diketone)trifluoroacetylacetone(HTfac)and the C=C=-containing neutral ligand 4-vp-2,2'-bpy(4-styryl dipyridine).Their structural characterization shows that the central metal ion Zn2+ of the Zn(L1)(4vp)monomer is a five-coordinate geometrical configuration and the functional double bond can be stably present.The centeral lanthanide ion of each of complexes 1-8 is a eight-coordinated geometrical configuration,from which,oscillator-vibrational luminescent quching is effectively decreased.The photophysical properties show that Zn(L1)(4vp)can emit yellow light with a quantum yield of 5.2%;complexes 2 and 3 can be sensitized by the same "antenna group" to emit pure red and green light,respectively.And their quantum yields were 16.2%and 0.2%,respectively.The complex 6 with one unsaturated double bond can emit pure red with a quantum yield of 20.8%.Secondly,according to the three primary colors(RGB:the red light of complex 2,the green light of 3 and the blue light of PVK)strategy to build white light,the white-light doped materials PVK@2@3 were synthesized by physical doping different proportions of 2,3 and PVK.Upon the molar ratio of(400:1[2/3 = 1:9])and the excitation wavelength of 366 nm,the high-quality white light can be obtained:x = 0.304 and y = 0.306 of CIE coordinate,84 of color rendering index CRI,6271 K of color temperature CCT and 11.2%of the quantum yield.In addition,for Poly(NVK-co-Zn(L1)(4vp)-co-6)100:1[Zn(L1)(4vp)/6=1:1])obtained by copolymerization of yellow-light Zn(L1)(4vp),the red light complex 6 and the blue light NVK,the excitation wavelength between 310-345 nm is found to produce the high-quality and stable white-light emission:the CIE coordinate of x = 0.331?0.334 and y = 0.362?0.363.When the excitation wavelength is 345 nm,the white-light is characteristic of CRI of 86,color temperature CCT of 4717 K and quantum yield of 13.2%,respectively.Through the control of the molar ratio(200:1[Zn(L1)(4vp)/6 = 1:1])and the excitation wavelength in the range of 318-378 nm,high-quality white-light emission:(CIE x = 0.297?0.330 and y = 0.311?0.371)is founded.Especially upon the excitation wavelength of 358 nm,the color rendering index CRI of 96,color temperature CCT of 5464 K and the quantum yield of 10.1%are obatined,respectively.Compared with monomers,not only the doping and metallopolymer-type white-light materials have better photophysical properties,but also their thermal stability and film properties are significantly improved. |
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