| Due to their widet application prospective in high definition display, integration optical system, solid-state laser, bio-analysis and medical diagnosis, it is of great significance to develop a control synthesis method of novel genres of phosphors and exploit novel type of fluorescent material. In the development of phosphors, it is essential to choose a proper interstitial substance, as the luminescence of adulteration ion will influenced on some characters of the radiation stroma, leading to the variation of luminescence characteristic. And also that the performance of synthesized phosphors can be affected by synthetic technique.It was found that borate stroma material has the characteristic of high brightness, low precessing temperature and easy synthesis from single-base double-doped phosphors, and it is considered as a radiation stroma with great practical value. Therefore, in recent years, more and more researches about phosphors through borate stroma have been carried out, which are mainly focussing on lanthanide borates phosphors. In luminescent materials, 4f layer electron of activation lanthanide ion provides energy levels high enough for electronic transition, which can produce a variety of colorful absorption, excitation and emission spectra ranging from vacuum ultraviolet to infrared spectral area. In these ions, the most important series are Eu3+, Tb3+,Sm3+. Hence, In this work, Eu3+ ,Tb3+,Sm3+ were selected as as dopants ion for phosphors.Solid state reaction and collosol-gelatin technique were utilized to improve the performance of phosphor and lanthanide borates phosphors composited by alkali metal Na3La(BO3)2:RE3+(RE=Eu,Tb,Sm),using misalignment crystalloid Na3La(BO3)2 as interstitial substance.In the preparing process of borate phosphors, appropriate ingredient inverse proportion and preparation condition were determined through solid state reaction and collosol-gelatin technique,and the volume ratio of material, reaction temperature and so on, which affected the target products, was analysed in accordance with reaction mechanism. X-ray diffraction (XRD) was used to characterize Na3La0.8Eu0.2(BO3)2, phosphors quenching curve was investigated and protracted accordingly. After that, excitation and emission spectra of Na3La(BO3)2:RE3+(RE=Eu,Tb,Sm) were measured and explained. The results showed that, when the excitation wavelength of Na3La0.8Eu0.2(BO3) and emission peak are under of 261 and around 617 nm, respectively, transition emission of 5D0-7F2 in Eu3+ion takes place, which belongs to strong red light-emission. The dominated red emission of Tb3+ corresponding to the electric dipole transition 5D4-7F5 is located at 544 nm in Na3La0.85Tb0.15(BO3)2. In contrast, bright the luminescence of Na3La0.85Sm0.15(BO3)2 attributed to the6G5/2-4H13/2 is located at 504 nm, which is the strongest emission for conventional red emission from Sm3+. XRD patterns of fluorescence of diffraction peaks show the high degree of crystallinity of phosphor,and the luminous efficiency of phosphor is high.In this work, lanthanide borates phosphors composited by alkali metal was studied, and a synthesis method of phosphors material was discussed, which paves the way for other novel borates phosphors. Relevant experimental data of synthesizing Na3La(BO3)2:RE3+(RE=Eu,Tb,Sm) provides a novel method for further synthesis of higher purity product. |
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