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荧光粉转化法是目前制备白光 LED 的主流技术.但是商业化的荧光粉由于缺少红色部分或红色不稳定,使得制备出的 LED 灯泡颜色偏冷,因此研制低成本、性能稳定的红色荧光粉具有重要的意义.本项目以化学性质稳定、合成工艺温和的硼酸盐 KZn4(BO3)3为基质,掺杂稀土离子来研究荧光粉的发光性能.通过高温固相法合成了一系列不同掺杂浓度的 KZn4(BO3)3∶Eu3＋,并测试了 XRD 衍射图谱,发射和激发光谱.研究表明 Eu3＋离子倾向于占据 Zn2＋格位.同时,KZn4(BO3)3∶Eu3＋的最佳激发波长(393 nm)位于近紫外波段,适于用近紫外 LED 芯片激发来制备 LED.KZn4(BO3)3∶Eu3＋的最强发射峰位于590 nm,属于5 D0-7 F1跃迁.当发生浓度猝灭时,Eu3＋-Eu3＋离子间的临界距离为3 nm.该荧光粉的色坐标为(0.6297,0.3699),色饱和较高.该物质是一种潜在的可被用于 LED 照明用的红色荧光粉.

Phosphor transformation is the main method of producing white-light LEDs.However, most phosphors in the market are lack of red component or color stability,because most commercial LEDs produce cool white light.Thus it is realistic to search for new red phosphors with high stability and low cost.In this regard,borates,chemical stable and easily productive,have attracted our atten-tion.The structure and photoluminescence properties of KZn4 (BO3 )3 doped with Eu3 + are analyzed. We have synthesized a series of KZn4 (BO3 )3 ∶Eu3 + with different doping concentration by solid state reactions.From the X-ray diffraction data,it is concluded that Eu3 + ions are inclined to occupy Zn2 +site in the structure of KZn4 (BO3 )3 .And the PLE indicates that the best exciting wavelength (393 nm)of KZn4 (BO3 )3 ∶Eu3 + is near ultraviolet,which makes it suitable for near-UV LEDs.According to the PL,the strongest peak locates at 590 nm which is ascribed to the transition of 5 D0 -7 F1 .In addition,the quenching concentration of Eu3 + is about 1.5%,and the critical distance is about 3 nm. Finally,the CIE coordinates of KZn4 (BO3 )3 ∶ Eu3 + is (0.629 7,0.369 9 ),which has high color saturation.The material is a potential red phosphor used for LEDs.