Preparation And Luminescence Of Dy³⁺/Eu³⁺/Tm³⁺ Doped Glass-Ceramics Containing ZnMoO₄

White light-emitting diode（w-LED）,as a new type of light-emitting device,has long service life,short response time,environmental protection,no pollution,small size and other excellent performances,is a very ideal new solid-state lighting source.At present,w-LED devices are usually composed of yellow phosphors excited by blue In Ga N chip,resulting in poor color rendering,high color temperature and poor thermal stability of devices.In order to solve the above problems,Dy³⁺single doped,Dy³⁺/Eu³⁺co-doped and Dy³⁺/Eu³⁺/Tm³⁺tri-doped glass ceramics containing ZnMoO₄were synthesized by melt-crystallization method.The crystal phase composition,microscopic morphology,light transmittance,excitation and emission spectra,fluorescence lifetime and variable temperature spectra of glass ceramics were discussed.The effect of doped ratio of rare earth ions on luminescence color of glass ceramics was studied.Combined with differential scanning calorimetry,X-ray diffraction,scanning electron microscopy and optical transmittance curves,the optimal heat treatment conditions of glass ceramics were discussed and analyzed.Finally,the optimal heat treatment conditions of Dy³⁺doped,Dy³⁺/Eu³⁺co-doped,Tm³⁺/Dy³⁺/Eu³⁺tri-doped glass ceramics were 620°C/3 h,620°C/1.5 h,610°C/1.5 h,respectively.The excitation wavelengths of Dy³⁺doped,Dy³⁺/Eu³⁺co-doped,Tm³⁺/Dy³⁺/Eu³⁺tri-doped were 387 nm,387 nm,358 nm,respectively.The emission spectra of each system were excited at this wavelength,and the optimal doped concentration of Dy³⁺doped,Dy³⁺/Eu³⁺co-doped,Tm³⁺/Dy³⁺/Eu³⁺tri-doped glass ceramics was determined as follows:0.4%Dy³⁺,0.4%Dy³⁺/0.7%Eu³⁺,0.5%Tm³⁺/0.8%Dy³⁺/1.2%Eu³⁺.Through the change of emission peak intensity,it was confirmed that there was energy transfer from Dy³⁺to Eu³⁺in Dy³⁺/Eu³⁺co-doped system.In Tm³⁺/Dy³⁺/Eu³⁺tri-doped system,there were energy transfer processes from Tm³⁺to Dy³⁺,Tm³⁺to Eu³⁺,and Dy³⁺to Eu³⁺.The thermal quenching characteristics of the samples were also studied.The luminescence color of the sample shows that the tunable white light emission has been realized,which has a wide application prospect in the field of w-LED.