水热法与固相法制备Ca2B5O9Cl:Eu光谱特性的研究

对比研究了制备方法(水热法与高温固相法)、激发条件、Eu离子浓度对Ca2B5O9Cl:Eu发光体光谱特性及制备条件对晶体形貌的影响.结果表明,水热法制备的Ca2B5O9Cl:Eu发光体在254 nm激发下主要以Eu3 的5D0→7FJ(J=1,2,3,4)跃迁发射为主,365 nm激发下则以Eu2 的4f65d1→8S7/2跃迁发射为主.高温固相法制备的发光体在365 nm激发下主要是Eu2 的4f65d1→8S7/2跃迁发射,而254 nm激发下Eu2 和Eu3 的发射均较弱.Eu浓度对Ca2B5O9Cl : Eu的光谱特性影响较小,而制备方法和激发条件却对其影响较大.SEM揭示了空气条件与还原气氛制备的产品结晶完美、表面光滑、颗粒度在0.82～1.06 μm之间.

Study on Spectral Properties of Ca2B5O9Cl:Eu Prepared with Hydrothermal Method and Solid Method

Effects of preparation methods (hydrothermal method and high temperature solid method), excitation condition, and Eu ions concentration on spectral properties of Ca2B5O9Cl : Eu phosphor were studied. The effects of preparation condition on crystal photographs were also discussed. The result showed that the Ca2B5O9Cl : Eu phosphors prepared with hydrothermal method had mainly 5 D0 --> 7F(J) (J = 1, 2, 3, 4) emission of Eu3+ with 254 nm excitation and 4 f6 5d1 --> 8S(7/2) emission of Eu2+ with 365 nm excitation, the one prepared with high temperature solid method had mainly 4 f6 5d1 --> 8S(7/2) emission of Eu2+ with 365 nm excitation and very weak emissions of Eu2+ and Eu3+ with 254 nm excitation. Eu ions concentration hardly affected spectral properties, but the preparation method and excitation conditions had remarkable influence on the properties. SEM revealed that the products prepared both in the air and reductive atmosphere had consummate crystal, slippery surface and appropriate size (0.82-1.06 microm).