Chen Nianmin, Wang Yunjian, Li Longfeng, Geng Lei, Zhang Maolin
Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, School of Chemistry and Material Science, Huaibei Normal University, Huaibei 235000, China.
College of Physics and Physical Engineering, Qufu Normal University, Qufu 273165, China.
Nanomaterials (Basel). 2023 Apr 24;13(9):1446. doi: 10.3390/nano13091446.
Designing phosphors that are excited by blue light is extraordinarily important for white light-emitting diodes (w-LEDs). In the present study, a new Ruddlesden-Popper type of SZO:Eu ( = 0.01~0.10) phosphors was developed using solid-state reactions. Interestingly, a Eu doping-induced phase transformation from the SrZrO (cubic) to the SrZrO (orthorhombic) phase was observed, and the impact of the occupied sites of Eu ions on the lifetime of SrZrO:Eu phosphors is discussed in detail. Diffuse reflectance spectroscopy results showed that the band gap of SZO:Eu phosphors gradually increased from 3.48 eV for undoped SrZrO hosts to 3.67 eV for SZO:0.10Eu samples. The fluorescence excitation spectrum showed that ultraviolet (300 nm), near-ultraviolet (396 nm) and blue light (464 nm) were all effective excitation pump sources of SrZrO:Eu phosphors, and the strongest emission at 615 nm originated from an electric dipole transition (D→F). CIE coordinates moved from orange (0.5969, 0.4267) to the reddish-orange region (0.6155, 0.3827), and the color purity also increased. The fabricated w-LED was placed on a 460 nm chip with a mixture of YAG:Ce and SZO:0.1Eu samples and showed "warm" white light with a color rendering index (CRI) of 81.8 and a correlation color temperature (CCT) of 5386 K, indicating great potential for application in blue chip white LEDs.
设计能被蓝光激发的荧光粉对于白光发光二极管（w-LED）来说极其重要。在本研究中，采用固态反应法制备了一种新型的Ruddlesden-Popper型SZO:Eu（= 0.01~0.10）荧光粉。有趣的是，观察到Eu掺杂导致从SrZrO（立方相）到SrZrO（正交相）的相变，并详细讨论了Eu离子占据位点对SrZrO:Eu荧光粉寿命的影响。漫反射光谱结果表明，SZO:Eu荧光粉的带隙从未掺杂的SrZrO基质的3.48 eV逐渐增加到SZO:0.10Eu样品的3.67 eV。荧光激发光谱表明，紫外光（300 nm）、近紫外光（396 nm）和蓝光（464 nm）都是SrZrO:Eu荧光粉的有效激发泵浦源，615 nm处最强发射源于电偶极跃迁（D→F）。CIE坐标从橙色（0.5969, 0.4267）移至红橙色区域（0.6155, 0.3827），色纯度也有所提高。将制备的w-LED与YAG:Ce和SZO:0.1Eu样品的混合物放置在460 nm芯片上，显示出“暖”白光，显色指数（CRI）为81.8，相关色温（CCT）为5386 K，表明在蓝光芯片白光LED中具有巨大的应用潜力。
