Fluorescent Color And Excitation Wavelength Dependency In Sm³⁺ And Dy³⁺ Doped Antimony Phosphate Glasses

The production and life of mankind can not be separated from the light source.New light source has always been the pursuit of mankind.Compared with the bulk and powder materials,the glass has the advantages of uniform,transparent,good mechanical properties,chemical stability and easy to be processed into various shapes.Among various glasses,phosphate glass with properties such as high solubility of rare earth,large cross section,high transparency and low preparation cost,making it a good host material,receives much attention.SbD3+ has a strong absorption in the UV region,and broad visible emission under UV excitation.Rare earth ions have abundant energy levels,which can not only affect the fluorescence behavior of Sb3+,but also can adjust the overall fluorescence colorn It is important to study the fluorescence color and excitation wavelength dependence of rare earth ions doped antimony phosphate glasses for the development of new luminescent materials and the further development and utilization of rare earth resources.This project reports the preparation of Sm3+/Dy3+ doped antimony phosphate(MSP)glasses and their thermal and optical properties,which are characterized by differential thermal analysis,absorption specrtrum,excitation spectrum and emission spectrum.The results are as follows:1.According to the molar host composition 5.11Na2O-0.85BaO-9.82Al2O3-13.84ZnO-5.02Sb2O3-55.36P2O5(MSP-1)and 17.17Na2O-0.97BaO-15.61ZnO-11.06Al2O3-5.66 Sb2O3-49.53P2O5(MSP-2),Sm3+ doped MSP-1 and Dy3+ doped MSP-2 glasses were prepared by traditional melt-quenching method with air condition.Additional Sm2O3(0.1 wt%,0.5wt%,1.0wt%and 2.0wt%)and Dy2O3(0.12wt%,0.36wt%,0.88wt%,1.44wt%and 3.90wt%)were introduced into the MSP-1 and MSP-2 glass composition,respectively,based on the host weight.Transition temperature(Tg)of MSP-1 and MSP-2 are derived to be 430? and 402?,respectively,and no crystallization onset point(Tx)are observed below the temperature of 650? and 570?,respectively,meaning that the temperature difference value(?T= Tx-Tg)is more than 220? and 160?,respectively,which implies MSP glasses hold good thermal stability and anti-crystallization ability at a large temperature range.2.Based on J-O theory,J-O intensity parameters of Sm3+ in MSP-1 glasses and Dy3+ in MSP-2 glasses were deduced from absorption spectra.The ?t(t=2,4,6)of Sm3+ in MSP-1 glasses are calculated to be 3.08×10-20,3.36×10-20 and 1.81×10-20 cm2,respectively;The ?t(t=2,4 and 6)of Dy3+ in MSP-2 glasses were calculated to be 5.74×10-20,1.47×10-20 and 1.12×10-20 cm2,respectively,which indicates a high asymmetrGcal and covalent environment around Sm3+/Dy3+ in the MSP glasses.The oscillator strengths,calculated radiative lifetime trad and fluorescence branching ratios ?ij were calculated based on J-O intensity parameters.And the results indicate warm fluorescence can be obtained effectively from Sm3+ and Dy3+doped MSP glasses.3.Under 200-320 nm ultraviolet(UV)radiation,broad visible emissions of Sb3+ in MSP glasses are observed and the full width at half maximum(FWHM)is 150 nm.The color coordinates are located near the edge between white light region and blue light region and the sample presents bluish-white light in the whole.The difference from emission spectra,spectral power distribution and color coordinate of the MSP matrix glass under different excitation show that the fluorescence color of the MSP matrix glass has a significant dependence on the excitation wavelength.The difference from the three aspects,emission spectra under different excitation,selective excitation spectra and fluorescence lifetimes indicates that there are heterogeneous Sb3+ luminescence centers in the MSP matrix glass.4.With concentration increase of Sm3+ and Dy3+ to 2.0wt%and 1.44wt%,respectively,emission intensity of Sb3+ weakens while emission intensity of Sm3+ and Dy3+ heightens.Correspondingly,luminescence color change from bluish-white to warm-white,indicating rare earth doping can tune fluorescence of MSP glass effectively.Under different excitations,Sm3+ and DL3+ doped MSP glasses exhibit different emission behavior and the sample shows stronger dependency of fluorescent color to excitation wavelength after rare earth ion doping.Tne comparison of emission decrease of Sb3+ and emission increment of rare earth ion after rare earth ion doping and improving rare earth doping concentration,the highly consistency of excitation spectra monitoring emission of rare earth ion and emission of Sb3+ during the excitation region of 200-320nl and remarkable decrease of lifetimie for Sb3+ after rare earth ion doping,indicate the exsitance of energy transfer between Sb3+ to Sm3+ and Dy3+.By selecting the appropriate excitation wavelength and optimizing the doping amount of Sm3+and Dy3+,it is possible to obtain strong polychromatic fluorescence emission in Sm3+ and Dy3+ doped MSP glasses,which provides the possibility for the development of high quality fluorescent devices.