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Luminescence behaviour of Mn(4+) ions in seven coordination environments of K3ZrF7
Huiying Tan1, Meizhu Rong, Yayun Zhou
1Key Laboratory of Comprehensive Utilization of Mineral Resource in Ethnic Regions, Joint Research Centre for International Cross-border Ethnic Regions Biomass Clean Utilization in Yunnan, School of Chemistry & Environment, Yunnan Minzu University, Kunming, 650500, P. R. China. wangzhengliang@foxmail.com xchow123@126.com.
Abstract:
A single-phased Mn(4+) doped fluorozirconate red phosphor, K3ZrF7:Mn(4+), has been successfully synthesized. Its structure, morphology, composition and optical properties were investigated by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic absorption spectroscopy, diffuse reflectance spectroscopy, photoluminescence spectroscopy and by using luminescence decay curves. It was found that Mn(4+) ions only coordinating with seven F(-) anions in a K3ZrF7 crystal field can possess intense red emission under blue light illumination. Mixing the obtained K3ZrF7:Mn(4+) red phosphor with commercial Y3Al5O12:Ce(3+) and coating the mixture on a blue-GaN chip, obvious warm white light with a low correlated color temperature (2970 K) and a high color rendering index (Ra = 91.4 and R9 = 72) were achieved from white light-emitting diode devices.
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