Synthesis and properties of Rb2GeF6:Mn4+ red-emitting phosphors
Synthesis and properties of Rb2GeF6:Mn4+ red-emitting phosphors
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DOI：
10.7567/jjap.57.022601
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发表时间：
2018-02-01
影响因子：
1.5
通讯作者：
Adachi, Sadao
中科院分区：
文献类型：
--
作者：
Sakurai, Shono;Nakamura, Toshihiro;Adachi, Sadao
采用共沉淀法合成了Rb 2GeF 6：Mn 4+红色荧光粉，并通过激光显微镜观察、X射线衍射（XRD）分析、光致发光（PL）分析、PL激发（PLE）光谱和PL衰减测量等方法研究了其结构和光学性质。制备了六棱锥形式的单晶锭，其基面直径近似为2 mm。XRD分析表明，Rb_2GeF_6为六方晶系（C-6v（4）= P_6（3）mc），a = 0.5955nm，c = 0.9672nm。该磷光体表现出强烈的Mn 4+相关的零声子线（ZPL）发射峰，通常在具有压电活性晶格（如六方晶格）的基质晶体中观察到。散装锭和粉末样品的量子效率分别为87和74%，几乎相同的发光衰减时间类似于6毫秒。确切的ZPL能量和相关的晶体场和拉卡参数从PL和PLE光谱通过弗兰克-康登分析。从T = 20至500 K，使用热猝灭模型，考虑玻色-爱因斯坦声子统计的温度依赖性的PL强度进行了分析。并对Rb_2GeF_6：Mn ~（4+）和Rb_2 MF_6：Mn ~（4+）（M = Si和Ti）的发光性能进行了比较。(C)2018日本应用物理学会
Rb2GeF6:Mn4+ red-emitting phosphors were synthesized by coprecipitation and their structural and optical properties were investigated by laser microscopy observation, X-ray diffraction (XRD) analysis, photoluminescence (PL) analysis, PL excitation (PLE) spectroscopy, and PL decay measurement. Single-crystalline ingots in the form of a hexagonal pyramid were prepared with a basal plane diameter of similar to 2mm. The XRD analysis suggested that Rb2GeF6 crystallizes in the hexagonal structure (C-6v(4) = P6(3)mc) with a = 0.5955nm and c = 0.9672 nm. The phosphor exhibited the strong Mn4+-related zero-phonon line (ZPL) emission peak typically observed in host crystals with piezoelectrically active lattices such as a hexagonal lattice. The quantum efficiencies of the bulk ingot and powdered samples were 87 and 74%, respectively, with nearly the same luminescence decay time of similar to 6 ms. The exact ZPL energies and related crystal-field and Racah parameters were obtained from the PL and PLE spectra by Franck-Condon analysis. Temperature-dependent PL intensities were analyzed from T = 20 to 500 K using a thermal quenching model by considering Bose-Einstein phonon statistics. A comparative discussion on the phosphor properties of Rb2GeF6:Mn4+ and Rb2MF6:Mn4+ with M = Si and Ti was also given. (C) 2018 The Japan Society of Applied Physics