白光LED用红色荧光粉Gd2Mo3O9：Eu3+的制备及表征

利用Na₂CO₃作为助熔剂,采用高温固相反应方法制备了三价铕离子激活的Gd₂Mo₃O₉红色荧光粉。利用XRD和荧光光谱,研究了助熔剂的量、制备时的温度以及激活剂Eu³⁺的浓度对荧光粉的晶体结构和发光性能的影响。测试结果表明,这种新型的荧光粉可以被紫外光280nm,近紫外光395nm和蓝光465nm有效激发,发射主峰位于613nm,并且证明Eu³⁺离子在晶体结构中占据了非反演对称中心的位置。395,465nm的吸收与目前广泛应用的紫外和蓝光LED芯片的输出波长相匹配。因此,这种荧光粉是一种可能应用在白光LED上的红色荧光粉材料。

Preparation and Properties of Red Emitting Phosphor Gd2Mo3O9∶Eu3+ for White LEDs

Eu³⁺-doped Gd₂Mo₃O₉ was prepared by solid-state reaction route using Na₂CO₃ as flux and characterized by powder X-ray diffraction.According to X-ray diffraction,this material is belongs to tetragonal system.The effects of flux content and sintering temperature on the luminescent properties were investigated by emission and excitation spectra.The results showed that flux content and sintering temperature have impact effects on the luminescent properties,the optimized flux content and the best sintering temperature is 3% and 800℃,respectively.The excitation and emission spectra also show that this phosphor can be effectively excited by C-T band(280nm),ultraviolet light 395nm and blue light 465nm.The wavelengths at 395nm and 465nm are nicely fitting in with the widely applied emission wavelengths of ultraviolet or blue LED chips.Integrated emission intensity of Gd₂Mo₃O₉:Eu is 2 times stronger than that of Y₂O₂S:Eu³⁺ under 395nm excitation.The Eu³⁺ doped Gd₂Mo₃O₉ phosphor may be a better phosphor candidate for solid-state lighting applications.