绿色荧光粉NaCaPO4：Tb3+的制备与发光特性

采用高温固相法合成了适用于UVLED芯片激发的NaCaPO₄:Tb³⁺绿色荧光粉并对其发光性质进行了研究。该荧光粉的发射峰位于418,440,492,545,586,622nm,分别对应Tb³⁺的⁵D₃→⁷F₅、⁵D₃→⁷F₄、⁵D₄→⁷F₆、⁵D₄→⁷F₅、⁵D₄→⁷F₄、⁵D₄→⁷F₃能级跃迁。其中位于492,545nm的发射峰最强,样品发射很好的绿光。主要激发峰位于380~400nm之间,属于4f→4f电子跃迁吸收,与UVLED芯片的发射相匹配。考察了Tb³⁺掺杂浓度和Li⁺,Na⁺和K⁺作为电荷补偿剂对样品发光性能的影响:Tb³⁺的最佳掺杂浓度为10%,以Li⁺的补偿效果最好。NaCaPO₄:Tb³⁺是一种适用于白光LED的绿色荧光材料。

Preparation and Luminescent Properties of Green NaCaPO4: Tb3+ Phosphor

The NaCaPO₄:Tb³⁺ green phosphor applicable for UVLED chip was synthesized by the general high temperature solid-state reaction and its luminescence properties were investigated. It shows six major emission peaks locating at 420,442,492,545,584 and 620 nm, which correspond to the ⁵D₃→⁷F₅, ⁵D₃→⁷F₄, ⁵D₄→⁷F₆, ⁵D₄→⁷F₅, ⁵D₄→⁷F₄ and ⁵D₄→⁷F₃ typical transition of Tb³⁺, respectively. The most intense peaks located at 492 nm and 545 nm and the phosphor shows excellent green emission. The excitation spectra contain a weak broad band extending from 200 to 280 nm and two peaks at 330~390 nm, which correspond well with the emission of UVLED (350~410 nm). The effects of doped-Tb³⁺ concentration and charge-compensating of Li⁺, Na⁺ and K⁺ on the emission intensity were also investigated. It shows that the optimum doped-Tb³⁺ concentration is 10% and Li⁺ gives the best improvement to enhance the intensity of the emission. The NaCaPO₄:Tb³⁺ is a potential green-emitting phosphor for white light emitting diode (W-LED).