Preparation And Infrared 2 ?m Luminescence Property Of?YLaZr?₂O₃ Powders Doped With Rare Earth

In recent years,2?m laser has received a lot of attention because of its extensive applications in the fields of medical,environmental protection,optical communication and national defense.In this paper,the ceramic powder of rare earth ion doped with?YLa Zr?₂O₃ was prepared by citrate method.The formation process,phase change,microstructure and luminescence properties of the powder were discussed,which was prepared for the following preparation of laser Y₂O₃ transparent ceramics.The main research results are as follows:?1?The effect of Tm³⁺ion and Yb³⁺ion concentration on the structure and luminescence properties of the powder was investigated by doping 0².5mol%Tm³⁺and 0¹0 mol%Yb³⁺in?YLa Zr?₂O₃ powder.It was found that all Tm³⁺ions and Yb³⁺ions were solidified into Y₂O₃ lattice,and did not reach the solid solution limit.The Tm³⁺had the highest emission at 1930 nm in the range of 1500²200 nm,corresponding to the Tm³⁺:³F₄?³H₆ energy level transition.The optimum doping concentration of Yb³⁺/Tm³⁺was 1 mol%and 2mol%respectively.The energy transfer process is that after Yb³⁺absorbs the energy of 980 nm LD pump,the electrons of Yb³⁺ions at²F_7/2/2 state are excited to the ²F_5/2/2 level through the ground state absorption process,and then transferred energy to the nearby ³H₅ metastable state of Tm³⁺ions by phonon-assisted energy-transfer process,then Tm³⁺ions are transferred from³H₅ to ³F₄ by non-radiation transition.Finally,The 1.93?m emission fluorescence are emitted from the Tm³⁺:³F₄?³H₆ transition.?2?The Ho³⁺and different sensitizing ions(Yb³⁺,Tm³⁺,Er³⁺)co-doped?YLa Zr?₂O₃ powder was respectively prepared by citrate method.The effect of doping concentration on the structure and luminescent property of the powder was also investigated.The results showed that the concentration of Ho³⁺ions in the concentration of 2 mol%could be solidified into Y₂O₃ lattice,and the solid solution limit of Yb³⁺ions must be more than 15 mol%.Otherwise,The solution limit of Tm³⁺ions was more than 3 mol%,and the solution limit of Er³⁺ions was greater than 2.5 mol%.?3?The Yb³⁺/Ho³⁺co-doped?YLa Zr?₂O₃ powder was prepared.Ho³⁺ions had broad emission bands in the range of 1800²200 nm,and the center wavelength was 2015 nm,corresponding to the Ho³⁺:⁵I₇?⁵I₈ energy level transition.Yb³⁺ions can significantly enhance the fluorescence intensity of Ho³⁺ions,and the optimum concentrations of Yb³⁺and Ho³⁺ions were 8mol%and 1 mol%,respectively.which is mainly attributing to the energy transfer between Yb³⁺:²F_5/2/2 and Ho³⁺:⁵I₆.The Tm³⁺/Ho³⁺co-doped?YLa Zr?₂O₃powder was prepared.The results showed that Tm³⁺ion can effectively sensitize Ho³⁺,the emission band was 1500²200 nm,and the center wavelength of Ho³⁺was 2015 nm,corresponding to Ho³⁺:⁵I₇?⁵I₈ energy level transition.The luminescence of Tm³⁺ions was inhibited by Ho³⁺luminescence,which beneficially enhanced the 2?m fluorescence emission of Ho³⁺.The emission band was 1500²200 nm,and the center wavelength of Ho³⁺was2015 nm,corresponding to Ho³⁺:⁵I₇?⁵I₈ energy level transition.Tm³⁺ions had strong emission intensity near 1.9?m,but it was inhibited by Ho³⁺ions.The optimum doping concentration of Tm³⁺/Ho³⁺ions was 1.5 mol%and 1 mol%respectively,which is mainly attributing to the effectively energy transfer between Tm³⁺:³F₄ and Ho³⁺:⁵I₇.The Er³⁺/Ho³⁺co-doped?YLa Zr?₂O₃ powder was prepared.The results showed that it could effectively energy transfer between Er³⁺/Ho³⁺ions,Moreover,Ho³⁺ions can suppress the fluorescence of Er³⁺ions at 1.5?m,in other words,the number of Er³⁺:⁴I_13/23/2 energy particles could be reduced.The optimum doping concentration of Er³⁺/Ho³⁺ions was 2mol%and 1 mol%respectively,which is mainly attributing to the effectively energy transfer between Er³⁺:⁴I_13/23/2 and Ho³⁺:⁵I₇.?4?The effect of Er³⁺ion and Yb³⁺ion concentration on the structure and luminescence properties of the powder was studied by doping 0.5³ mol%of Er³⁺and 0¹5 mol%of Yb³⁺in?YLa Zr?₂O₃ powder.It was found that all Er³⁺ions and Yb³⁺ions were solid-dissolved into Y₂O₃ lattice,and did not reach the solid solution limit.The Er³⁺had the highest emission at 1542 nm in the range of 1500¹700 nm,corresponding to Er³⁺:⁴I_13/2?⁴I_15/25/2 energy level transition.The optimal doping concentration of Er³⁺ions was 2 mol%.After codoping Yb³⁺ions,the luminescent intensity of the powders was enhanced and the energy transfer between Yb³⁺/Er³⁺ions could be carried out.The optimum doping concentration of Yb³⁺/Er³⁺was 3 mol%and 2 mol%respectively,which is mainly attributing to the effectively energy transfer between Yb³⁺:²F_5/2/2 and Er³⁺:I_11/2.?5?The effects of La₂O₃ and Zr O₂ contents on the luminescent intensity of Yb³⁺/Ho³⁺co-doped?YLa Zr?₂O₃ powder and Er³⁺co-doped?YLa Zr?₂O₃powder were studied.The addition of La₂O₃ leaded to lattice expansion,and the addition of Zr O₂ can cause lattice shrinkage.Both of the addition of La₂O₃ and Zr O₂reduced the 2.1?m luminescence of Ho³⁺/Yb³⁺.The appropriate amount of Zr O₂ could contribute to the 1.5?m luminescence of Er³⁺ions,and the best doping concentration of Zr⁴⁺ions was 3 mol%.However,The 1.5?m luminescence of Er³⁺ions could be inhibited by La₂O₃.