Department of Physics, Indian Institute of Technology (Indian School of Mines), Optical Materials and Bio-imaging Research Laboratory, Dhanbad, 826004, India.
Raja Ramanna Centre for Advanced Technology Indore, 452013, India.
Phys Chem Chem Phys. 2023 Apr 26;25(16):11756-11770. doi: 10.1039/d3cp00265a.
Herein we report the solution-combustion-method-synthesized Tb- and Tb/Yb-doped GdGaO nanophosphors, which possess luminescent and magnetic properties. The phase formation/crystal structure, and morphology of the prepared nanophosphors are studied using X-ray diffraction (XRD)/Raman spectroscopy and a field emission scanning electron microscope (FE-SEM), respectively. Tb/Yb-doped phosphor samples exhibit green emission with an intense band around 544 nm through downshifting (DS) and upconversion (UC) processes because of the D → F transition of Tb. In addition to this visible emission, these samples also show a NIR emission band around 1024 nm the quantum cutting (QC) process due to the F → F transition of Yb. Emission decay measurements of the D → F transition of Tb are performed to obtain the rate of energy transfer from Tb to nearby Yb. Furthermore, using this energy transfer, the quantum cutting efficiencies were estimated. For their practical application, a selected sample was used to fabricate a LED device by combining the sample with a UV-C LED (274 nm). The obtained results, such as the activation energy (∼0.20 eV) and the high CRI value (78), suggest that the prepared sample can be utilized as a green-light-emitting agent in phosphor-coated (pc) WLEDs.
在此，我们报告了采用溶液燃烧法合成的 Tb 和 Tb/Yb 掺杂 GdGaO 纳米荧光粉，其具有发光和磁性。通过 X 射线衍射（XRD）/拉曼光谱和场发射扫描电子显微镜（FE-SEM）分别研究了所制备的纳米荧光粉的相形成/晶体结构和形态。由于 Tb 的 D→F 跃迁，Tb/Yb 掺杂荧光粉样品通过下转换（DS）和上转换（UC）过程显示出强烈的 544nm 附近的绿光发射。除了这种可见发射之外，这些样品还显示出大约 1024nm 的近红外发射带，这是由于 Yb 的 F→F 跃迁的量子裁剪（QC）过程。进行 Tb 的 D→F 跃迁的发射衰减测量，以获得能量从 Tb 到附近 Yb 的转移速率。此外，利用这种能量转移，估算了量子裁剪效率。为了实际应用，选择了一个样品，通过将样品与 UV-C LED（274nm）结合，来制备一个 LED 器件。所获得的结果，例如激活能（约 0.20eV）和高 CRI 值（78），表明所制备的样品可用作磷光体涂层（pc）WLEDs 中的绿光发射剂。
