【摘要】 <正> Ce³⁺离子有一个宽而强的4f-5d吸收带,它能有效地吸收能量。Ce³⁺离子的荧光寿命非常短,能将能量有效地传递给其它离子起敏化作用。对于Ce³⁺→Tb³+),Ce³⁺→EU³⁺和Ce²⁺→Mn³⁺的敏化作用已有许多报导,并在灯用发光材料上获得应用。Blasse等提出在Ce³⁺敏化Tb³⁺时。用Gd³⁺作中间体能获得高效发光材料。由于Ce³⁺的5d能级强烈地依赖于基质,其发射波长可以从紫外到红区,而Gd³⁺的4f-4f跃迁的激发和发射峰值随基质的变化改变不大,因此将有可能呈现不同的Ce³⁺-Gd³⁺的能量转移过程。更多还原

【Abstract】 (Y_1-x-y Gd_xCe_y) BO₃ and (La_1-x-yGd_xCe_yMg)B₅O₁₀ are different in structure and havebeen synthesized by solid state reactions. Their spectroscopic properties have been studied.The energy transfer between Ce³⁺ and Gd³⁺ in different borate matrix is quite different. In(Y_1-x-yGd_xCe_y)BO₃ the 5d state of Ce³⁺ lies lower in energy than ⁶I and ⁶P levels of theGd³⁺, so Gd³⁺ in its excited state can thansfer its energy to Ce³⁺; whereas in(La_1-x-yGd_xCe_y Mg)B₅O₁₀ the 5d state of Ce³⁺ lies higher in energy than ⁶I and ⁶P levels of Gd³⁺ andvery close to ⁶I, the main excited state of Gd³⁺, hence Ce³⁺ can effectively transfer itsexcited energy to Gd³⁺. Accordingly, the energy transfer between Ce³⁺ and Gd³⁺ is mainlydetermined by the position of Ce³⁺ enrgy levels in different hosts.更多还原