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中文摘要：
采用高温固相法合成了 Na2Ca1–xSiO4：xCe3＋蓝色发光材料，并对其发光特性进行了研究。测得激发光谱为双峰宽谱，峰值分别位于 279nm 和360 nm，属于 Ce3＋的 4f–5d 跃迁，可被紫外–近紫外 LED 芯片有效激发。样品的发射光谱为不对称单峰宽谱，主峰位于 439nm。利用 van Uitert 公式证明了 Ca 在 Na2CaSiO4中只存在一种晶体学格位，判定经 Gauss 分峰拟合后的 425 nm 与 460 nm 子发射峰均来自于八配位 Ce3＋的发射，非对称发射的原因是局部晶体场的不对称和 Ce3＋能级劈裂。研究了 Ce3＋掺杂量对 Na2Ca1–xSiO4：xCe3＋材料发光特性的影响。结果显示，随 Ce3＋掺杂量的增大，发光强度先增大后减小，且发射光谱红移。Ce3＋掺杂量为 4% （摩尔分数）时，出现浓度猝灭，根据 Dexter 理论分析猝灭机理为电偶极–电四极相互作用。
英文摘要：
A blue phosphor of Na2Ca1-xSiO4：xCe3＋ was prepared by a solid-state method at high temperature. The luminescence char- acteristics of the prepared sample were investigated. The sample appears one asymmetrical emission band at 439 nm, which can be divided into two bands by the Gaussian fitting. The excitation spectrum has two broad bands at 279 nm and 360 nm, belonging to 4f-5d transitions of Ce3＋. The crystallographic sites of Ca2＋ in Na2CaSiO4 were analyzed. There exists only one Ca site in Na2CaSiO4 crystal, which can be calculated by the van Uitert formula. Therefore, the divided emission bands located at 425 nm and 460 nm both originate from the Ce3＋ center of the eight coordinate. The dissymmetrical emission band of Na2CaSiO4：Ce3＋ phosphor is caused by asymmetry of the local crystal field and Ce3＋ ion energy level splitting. The effect of Ce3＋ concentration on the luminescent intensity of Na2Ca1-xSiO4：xCe3＋ phosphor was investigated. The result shows that the luminescent intensity first increases and then decreases with increasing of Ce3＋ concentration, and reaches the maximal value at 4% in mole. The concentration quenching mechanism is due to the electric dipole-electric quadrupole interaction from the Dexter theory.
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