Study Of The Rare Earth Co-doped Ba₃YPO₃/Ba₂Li₃?PO₃?₇ And Mg_0.5Ti₂?Po₄?₃ Phosphor

The synthesis method and preparation process of phosphate phosphors are relatively easy,and the phosphors are very good in stability and luminescence efficiency.Therefore,phosphate phosphors have been widely and deeply studied.These phosphors have also achieved good application effects in the fields of light emission and display.In this paper,the preparation process and properties of several rare earth doped phosphates were studied.The energy transfer between rare earth ions was studied.In the paper,the main content is that Tm³⁺/Dy³⁺and Eu³⁺/Tb³⁺rare-earth ions are incorporated into the Ba₃YPO₃/Ba₂Li₃?PO₃?₇ and Mg_0.5Ti₂?PO₄?₃ by high-temperature solid-state method to prepare rare earth-doped Ba₃Y_1-x-yPO₃:xTm³⁺,yDy³⁺and Ba_2-x-yLi₃?PO₃?₇:xEu³⁺,yTb³⁺and Mg_0.5-x-yTi₂?PO₄?₃:xTb³⁺,yEu³⁺phosphors.Their respective luminescence properties,quenching concentrations of Tm³⁺and Eu³⁺ions,energy transfer between Tm³⁺/Dy³⁺in the host of Ba₃YPO₃ and energy transfer between Eu³⁺/Tb³⁺in Ba₂Li₃?PO₃?₇ and Mg_0.5Ti₂?PO₄?₃ were studied in more detail.The CIE of these synthesized phosphors were studied and analyzed.The results shows that these materials have great potential as phosphor materials for LEDs.First of all,experimental studies of Ba₃YPO₃ single-doped Tm³⁺and co-doped Tm³⁺/Dy³⁺luminescence materials were performed by high temperature solid-state method.and their emission spectra and excitation spectra were measured.By analyzing the emission spectra of single-doped Tm³⁺ions,it can be found that the concentration of the emission intensity of the Tm³⁺ion doped into the Ba₃YPO₃ host is 10%mol,which is the quenching concentration.The quenching mechanism of Tm³⁺ions in Ba₃YPO₃ host was studied and analyzed.It was confirmed that the quenching mechanism of Tm³⁺ions is related to the dipole-dipole interaction of Tm³⁺ions.There is an energy transfer phenomenon between Tm³⁺and Dy³⁺ions in the Ba₃YPO₃,and the reason for the energy transfer in the Ba₃Y_1-x-yPO₃:xTm³⁺,yDy³⁺is due to he dipole-dipole interaction between Tm³⁺and Dy³⁺ions.By adjusting the excitation wavelength?350 nm,353 nm,359 nm,and 363 nm?and doping concentration of the rare earth ions,the CIE of the Ba₃Y_1-x-yPO₃:xTm³⁺,yDy³⁺sample can transition from the blue,white and then to yellow light region.The emission points are?0.326,0.327?when the Ba₃Y_0.93PO₃:0.03Tm³⁺,0.04Dy³⁺are excited at 350 nm,which is very close to the ideal white color coordinates?0.33,0.33?.The research results indicate that the Ba₃Y_1-x-y?PO₄?₃:xTm³⁺-yDy³⁺phosphors may be a promising single-component phosphor in the field of solid state lighting.Secondly,the Ba_2-x-yLi₃?PO₃?₇:xTb³⁺,yEu³⁺luminescence materials are also prepared by the high temperature solid phase method.The excitation and emission spectra of single-doped Eu³⁺and co-doped Eu³⁺/Tb³⁺samples were measured and analyzed.In the experiment,it was found that the quenching concentration of Eu³⁺ion doping into the host of Ba₂Li₃?PO₃?₇ was 25%mol.The quenching mechanism of Tm³⁺ions in Ba₂Li₃?PO₃?₇ host was studied and analyzed.It was confirmed that the quenching mechanism of Tb³⁺ions is related to the dipole-quadrupole interaction of Tb³⁺ions.The detailed analysis of the excitation and emission spectra of Ba_2-x-yLi₃?PO₃?₇:xTb³⁺,yEu³⁺samples and the test results of Tb³⁺and Eu³⁺ions time decay curves can further prove that the energy transfer exsist between Tb³⁺and Eu³⁺ions.and the reason for Tb³⁺and Eu³⁺ions energy transfer in the Ba₂Li₃?PO₃?₇ host is due to the dipole-quadrupole interactions between the Tb³⁺ions and Eu³⁺ions.The color coordinate areas of the Ba_2-x-yLi₃?PO₃?₇:xTb³⁺,yEu³⁺phosphor can be distributed in the green,red,and yellow regions by effectively adjusted the excitation wavelength and doping concentration of Tb³⁺and Eu³⁺.The research results indicate that the Ba_2-x-yLi₃?PO₃?₇:xTb³⁺,yEu³⁺phosphors may be a promising single-component phosphor in the field of solid state lighting.Thirdly,the Mg_0.5-x-yTi₂?PO₄?:xTb³⁺,yEu³⁺luminescence materials are also prepared by the high temperature solid phase method.The excitation and emission spectra of single-doped Eu³⁺and co-doped Eu³⁺/Tb³⁺samples were measured and analyzed.The detailed analysis of the excitation and emission spectra of Mg_0.5-x-yTi₂?PO₄?:xTb³⁺,yEu³⁺samples and the test results of Tb³⁺and Eu³⁺ions time decay curves can further prove that the energy transfer exsist between Tb³⁺and Eu³⁺ions.and the reason for Tb³⁺and Eu³⁺ions energy transfer in the Mg_0.5Ti₂?PO₄?host is due to the dipole-quadrupole interactions between the Tb³⁺ions and Eu³⁺ions.The color coordinate areas of the Mg_0.5-x-yTi₂?PO₄?:xTb³⁺,yEu³⁺phosphor can be distributed in the purple,purplish,pink and reddish orange regions by effectively adjusted doping concentration of Tb³⁺and Eu³⁺.The research results indicate that the Mg_0.5-x-yTi₂?PO₄?:xTb³⁺,yEu³⁺phosphors may be a promising single-component phosphor in the field of solid state lighting.