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单离子掺杂体系单一基质白光荧光粉可以有效克服紫外芯片+三基色荧光粉获得白光方案中颗粒分散性和沉降性不均的问题, 克服荧光粉彼此间发光再吸收及三基色配比调控等问题. 本文采用熔融盐法制备了Sm3+离子单掺NaLa(WO4)2:x Sm3+白光荧光粉. 在紫外光激发下,
\rmWO_4^2- 自激活发出的蓝绿光, 与Sm3+发射的绿光、黄光、橙光和红光混合得到了白光. 在250 nm激发下, 荧光粉会发出冷白光; 在403 nm激发下会发出暖白光. 随着Sm3+掺杂浓度增加, 相对色温逐渐降低. 所制备的样品均为纯的四方相结构, 晶粒形貌为不规则菱形薄片. 通过分析实验数据确定Sm3+离子间的能量猝灭类型为电偶极-电偶极作用. 得到的NaLa(WO4)2: x Sm3+荧光粉具有较高的稳定性, 能被近紫外LED芯片有效地激发, 可作为单离子掺杂单一基质白光荧光粉潜在候选.-
关键词:
- NaLa(WO4)2: Sm3+ /
- 光致发光 /
- 白光荧光粉
Single ion doped single phase white emitting phosphors have some special advantages and great potential applications in the field of high quality LED lighting. This type of phosphors can effectively solve the problem of uneven particle dispersion and sedimentation in the white light scheme obtained by UV chip plus trichromatic phosphor, and solve the problems of the luminescence and reabsorption between phosphors and the regulation of trichromatic ratio. A comparison of the single-ion doping luminescent material with the multi-ion doping system shows that the single-ion doping luminescent material is simpler in both preparation process and luminescence color adjustment, which can achieve higher color rendering index, more easily controlled color temperature and closer to the color coordinates of white light.According to the principle of colorimetry and luminescence, light of two or more wavelengths may be combined to obtain white light emission. Under the UV excitation, the Sm3+ ions emit relatively strong green, yellow, orange and red light at 580–670 nm. Under UV excitation, the broadband spectrum of\rmWO_4^2- self-activated emission covers almost the whole visible region, but the blue-green light is strong in the short wavelength region and the yellow-orange-red light is weak in the long wavelength region. When Sm3+ ions are doped into tungstate, Sm3+ ions’ luminescence can effectively supplement the weak luminescence intensity of tungstate in the long-wave region, and white light can be obtained. Under the excitation of 250 nm, the phosphor emits cold white light, and warm white light under the excitation of 403 nm. The experimental results show that Sm3+ ions have a significant effect on the correlated color temperature adjustment of self-activated luminescence of NLW phosphors. All the prepared samples are crystallized into the tetragonal crystal phase structures and that their morphologies present rhombic sheet. By analyzing the experimental data, the type of energy transfer between Sm3+ ions is determined to be electrical dipole–electrical dipole interaction. The NLW: xSm3+ phosphor has high stability and can be effectively excited by ultraviolet/near-ultraviolet light, which can be used as a potential candidate of single matrix single-ion doped white phosphors.-
Keywords:
- NaLa(WO4)2: Sm3+ /
- photoluminescence /
- white light phosphors










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