共沉淀法合成CaO：Eu^3＋红色荧光粉的研究

Study on luminescent properties of red phosphor CaO:Eu^(3+) prepared by co-precipitation method

采用共沉淀法合成CaO:Eu3+红色荧光粉,探讨了Eu3+离子的掺杂量、煅烧温度和煅烧时间对样品发光性能的影响,并利用X-射线衍射仪(XRD)、扫描电镜(SEM)和荧光光度仪(PL-PLE)等仪器对样品的性能进行表征。结果表明:掺杂Eu3+作为发光中心进入到CaO基质的晶格中,其最佳掺杂量为1.5%(摩尔含量);最佳煅烧温度和煅烧时间分别为1100℃和4h;样品的激发峰位于200~290nm之间,对应于Eu3+-O2-的电荷迁移跃迁(CTB),属于宽带激发;Eu3+离子主要占据严格对称的格位,其最大发射峰位于592nm,对应于5D0→7F1磁偶极跃迁,属于红色发光。

The red phosphor CaO： Eu^3＋ was synthesized by co-precipitation method and characterized by XRD, SEM and PL-PLE. Also, the effects of doping concentration of Eu^3＋ , firing temperature and time on luminescent properties were investigated. The results showed that the Eua＋ ions as a luminescent center substituted Ca^2＋ sites without changing the crystal structure of cubic CaO. The optimum content of Eu^3＋ , the best sintering temperature and time was 1.5% （mol）, 1100℃ and 4h, respectively. This phosphor could be excited by an intense band from 200nm to 290nm, which was attributed to the charge transfer transition of Eu^3＋ --O2^- . The maximum emission wavelength was 592nm, corresponding to magnetic dipole transitions ^5D0→7 F1 of Eu^3＋ , indicting that Eu^3＋ ions mainly locate in strict symmetric position of the crystal lattice and the sample belonged to red luminescence.