Energy transfer and tunable emission in BaSrGdO:Bi,Eu phosphors for warm WLED

• Published in: Dalton transactions : an international journal of inorganic chemistry Vol. 52; no. 47; pp. 17966 - 17973
• Main Authors: Wei, Shuai, Lyu, Zeyu, Sun, Dashuai, Luo, Pengcheng, Lu, Zheng, Zhou, Luhui, He, Mingrui, Shen, Sida, You, Hongpeng
• Format: Journal Article
• Published: 05.12.2023
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/d3dt03126h

In this work, a series of BaSrGd 4 O 8 : x Bi 3+ blue phosphors was synthesized employing the high-temperature solid-state method. Phase purity of the samples was verified by X-ray diffraction and Rietveld refinement. Time-resolved photoluminescence spectra revealed the existence of two distinct Bi sites. Subsequent optimization of dopant types and doping levels in the batch led to an almost twofold increase in quantum efficiency. The introduction of Eu 3+ into the phosphors facilitated the construction of an energy transfer pathway. As the concentration of Eu 3+ was increased, the emission color changed from blue to purple and finally to red. In addition, the thermal stability and potential applications of the phosphors were extensively investigated. Finally, two WLED devices were successfully fabricated with color rendering indices of 96.27 and 92.18, and correlated color temperatures of 5198 and 2475 K. This underscores the prospective application of these phosphors in the field of high-quality warm WLEDs. A series of new phosphors BaSrGd 4 O 8 :Bi 3+ ,Eu 3+ achieved can be enhanced luminescence, energy transfer modulation of luminescence color, and used in WLED.