ABSTRACT To solve the problem of multiphased commercial light emitting diodes, a series of new single-phased BaLaAlO4:Dy3+ nanophosphors emitting cool white light were successfully fabricated via an energy-efficient approach, namely, solution combustion. X-ray diffractometry and Rietveld refinement revealed orthorhombic phase purity with P 212121(19) space group. Agglomerated orthorhombic nanoparticles (30–50 nm) were reported via scanning and transmission electron microscopy, whereas elemental distribution was confirmed by energy dispersive X-ray analysis. On excitation by 349 nm light, the nanophosphors showed peaks at 481 nm (blue color) on account of magnetic dipole transition and 573 nm (yellow color) by reason of electric dipole transition. Maximum intensity was observed for 3.0 mol% concentration of Dy3+ ions above which concentration quenching occurred due to electric multipolar interactions. Decay lifetime and energy band gap for optimized nanophosphor (BaLa1−x Dy x AlO4 (x = 3.0 mol%)) were obtained as 0.651 ms and 5.41 eV, respectively. CIE coordinates (0.297, 0.283), color purity (25.44 × 10−2), and correlated color temperature (CCT) value (8480 K) of optimal nanophosphor were found approximate to white coordinates of commercial LEDs and National Television System Committee, which proved their emission of cool white light and suggested their use in the outdoor lighting devices, i.e., white light emitting diodes.

中文翻译：

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燃烧合成法制备单相 BaLaAlO4:Dy3+ 纳米磷光体

摘要 为了解决多相商用发光二极管的问题，通过节能方法，即溶液燃烧，成功制造了一系列新的单相 BaLaAlO4:Dy3+ 纳米荧光粉，发出冷白光。X 射线衍射和 Rietveld 精修显示正交相纯度与 P 212121(19) 空间群。通过扫描和透射电子显微镜报道了聚集的正交纳米粒子（30-50 nm），而元素分布通过能量色散 X 射线分析证实。在 349 nm 光激发下，由于磁偶极子跃迁，纳米磷光体在 481 nm（蓝色）处出现峰值，由于电偶极子跃迁而在 573 nm（黄色）处出现峰值。观察到最大强度 3。Dy3+ 离子的 0 mol% 浓度高于该浓度会由于电多极相互作用而发生浓度猝灭。优化的纳米磷光体 (BaLa1-x Dy x AlO4 (x = 3.0 mol%)) 的衰减寿命和能带隙分别为 0.651 ms 和 5.41 eV。发现最佳纳米磷光体的 CIE 坐标 (0.297, 0.283)、色纯度 (25.44 × 10−2) 和相关色温 (CCT) 值 (8480 K) 接近商用 LED 和国家电视系统委员会的白色坐标，这证明它们发出冷白光，并​​建议将它们用于户外照明设备，即白光发光二极管。