Study On Rare Earth And Bismuth Luminescent Materials Based On Metallic Oxide

With the rapid development of industry,energy and environment problems have endangered the sustainable development of human society.Lighting devices will consume large amounts of energy every day,and the development of lighting devices with energy saving and green will greatly save energy consumption.Light emitting diode（LED）has become the fourth generation of lighting sources because of its energy-saving,long life,environmental protection and non-toxic characteristics.This thesis prepared Tb SSA@Zn O/Sn O₂,Ln(Dy³⁺,Eu³⁺and Tb³⁺)-Bi₂（PTA）₃/Bi₂O₃ and Ln(Eu³⁺and Tb³⁺)-Gd₂（BTC）₃/Gd₂O₃ composites,and the luminescence properties,structural morphology and their application in LED field were studied.The specific research contents are as follows:A kind of wire-in-tube structure Tb SSA@Zn O/Sn O₂ green phosphor was prepared by the template-hydrothermal method.As the shell,Zn O/Sn O₂ tightly wraped the core of Tb complex to form an interesting core-shell structure.Due to the strong absorption to ultraviolet light by Zn O/Sn O₂ and Tb complexes,and the"antenna effect"from the sodium sulfosalicylate（SSA）ligands,the Tb SSA@Zn O/Sn O₂ phosphor showed very strong green light emission at 543 nm.The Tb SSA@Zn O/Sn O₂ phosphor showed zero-thermal-quenching property,which was extremely rare for lanthanide complexes.The Tb SSA@Zn O/Sn O₂ green phosphor was mixed with the commercially available blue and red phosphors,and the excellent warm white LED（w-WLED）devices was obtained.Under the current of 20-120 m A,the performances of the LED device were still stable,which meeted the requirements of the high-power LED and had the great application value in the solid-state lighting field.Ln(Dy³⁺,Eu³⁺and Tb³⁺)-Bi₂（PTA）₃/Bi₂O₃ composite with rod-like morphology was prepared by one-step hydrothermal method.Due to the strong absorption to ultraviolet light of Bi₂O₃ and PTA,the reduced energy loss from the radiation transition of the ligand triplet by the strong absorption of Bi₂O₃ to the blue region（400-450 nm）,and the"antenna effect"of the ligand,the phosphor showed the strong characteristic emission of Ln³⁺.Dy³⁺single-doped phosphor showed the pure white light emission characteristics,and the fluorescence emission could be adjusted to obtain the warm white light emission through the co-doping of Dy³⁺and Eu³⁺.The light color could be adjusted from red light to green light by the co-doping of Eu³⁺and Tb³⁺.This series of phosphors achieved warm white light emission through the single phosphors excited by UV-light,which had a broad application prospect in the solid state lighting field.A kind of lamellar morphology Ln(Eu³⁺and Tb³⁺)-Gd₂（BTC）₃/Gd₂O₃ phosphor was prepared by template-hydrothermal method.The content of 1,2,4-benzenetricarboxylic acid（BTC）ligand had a great influence on the formation of the lamellar morphology of the composite.Through the strong absorption to UV light of Gd₂O₃ and BTC,the phosphor showed the strong characteristic emission of Ln³⁺.The warm white light emission could be realized by the co-doping of Eu³⁺and Tb³⁺combined with the blue light emission from BTC,and the fluorescence emission of the sample moved from the red light region to the green light region with the increase of Tb³⁺doping concentration.The Ln(Eu³⁺and Tb³⁺)-Gd₂（BTC）₃/Gd₂O₃ phosphor had the great practical practical value in LED field.