Preparation And Luminescent Properties Of Rare Earth Doped Fluorine Oxides And Fluoride Phosphors

Rare earth oxyfluoride and its fluoride,due to its low phonon energy,suitable trivalent rare earth ion doping level and stable chemical properties,make it a good rare earth doping matrix for various fields,such as luminescent materials,fluorescent probes and bio-labels have been widely explored in the field of luminescence.Based on the premise of oxyfluoride and fluoride as the matrix,we have designed a variety of synthetic strategies to obtain oxyfluorides and fluorides with different morphologies,sizes and special structures.With its excellent doping position,a variety of luminescent phosphors are obtained by single doping,double doping,and triple doping.The following is the general work of the paper:1.Y₂?OH?₅Cl·1.5H₂O with unique layered structure and cationic framework was synthesized by hydrothermal route.Y₂?OH?₅Cl·1.5H₂O was used as a self-sacrificial precursor to react with ammonium fluoride to obtain the intermediate product of hexagonal phase Y?OH?_xF_3-xby ion exchange.After calcination,Y₆O₅F₈?V-YOF?fluorescence material of orthogonal crystal system was obtained.Polychromatic phosphors from green to red are obtained by Tb³⁺,Eu³⁺co-doping and energy transfer between them.2.The pure hexagonalphase Y?OH?_1.57F_1.43 precursor was synthesized by hydrothermalprocess,and precursor withvarious morphologies and sizeswere obtained by changing the pH of the solution to 8-10 and replacing different fluorine sources?NH₄F?KF?NH₄F?.Y₅O₄F₇?V-YOF?:0.01Tm³⁺,0.045Dy³⁺white phosphor was obtained by co-doping Dy³⁺,Tm³⁺ions.3.Unconventional rare earth fluoride(Na_0.39Y_0.61F_2.35)phosphors were synthesized by facile hydrothermal process.In the synthesis process,trisodium citrate was used as the organic ligand in the reaction process,and then the pH of the abovesolution was adjusted to 10 by NaOH aqueous solution.Multicolor phosphor was obtained by Tb³⁺,Eu³⁺co-doping and Dy³⁺,Tb³⁺,Eu³⁺tri-doping and the energy transfer from Tb³⁺and Eu³⁺in the in the co-doped and tri-doped systems was explored was investigated.