摘要
采用高温固相法在还原气氛中合成NaxK1-xBa1-0.02PO4:0.02Eu2+(x=0.0,0.2,0.4,0.8,1.0)蓝色荧光粉,研究Na/K摩尔比对基质骨架晶体结构和对荧光粉发光性能的影响。结果表明,改变Na/K摩尔比会使荧光粉的晶体结构发生变化,当Na+的摩尔分数x=0时,样品为纯相的KBa PO4晶体,属于斜方晶系,当x≥0.6时,样品为纯相的Na Ba PO4晶体,属于单斜晶系;随着x的增大,样品的X射线衍射(XRD)峰向大角度方向偏移。NaxK1-xBa1-0.02PO4:0.02Eu2+的激发光谱为210~400 nm的宽带,最大激发波长在270 nm左右,其发射光谱为430~560 nm的宽带,最大发射波长位于443 nm左右,当Na/K为0.6/0.4时,荧光粉的发光强度最大;利用Van Uitert经验公式计算了Eu2+取代Ba2+时所占晶体学格位,得出441、471 nm两个发射分别属于八配位和六配位的Eu2+的4f65d1-4f75d0跃迁发射。采用高温固相法在还原气氛中合成Na0.6K0.4Ba1-x-0.02CaxPO4:0.02Eu2+(x=0.00,0.01,0.03,0.05,0.07,0.09,0.11)蓝色荧光粉,研究掺杂Ca2+以及改变焙烧温度对荧光粉发光性能的影响。结果表明,荧光粉的发射光谱为415~575 nm的宽带,属于Eu2+的4f65d1-4f75d0跃迁发射,发射峰位于443 nm左右,当x=0.07时,荧光粉的发光强度最大;掺入Ca2+和改变焙烧温度没有使荧光粉的晶体结构与发射光谱的形状发生明显的改变,但均可有效地提高荧光粉的发光强度。
The blue light-emitting phosphors NaxK1-xBa1-0.02PO4：0.02Eu^2＋（x=0.0,0.2,0.4,0.8,1.0） are synthesized by the high-temperature solid-state method under the reducing atmosphere. The effects of Na^＋/K^＋ mole ratio changing on matrix crystal structure and spectra properties of the phosphorsare are investigated. The results indicate that with the mole ratio of Na/K changes, the crystal structure of the phosphors changes. The phosphor shows orthorhombic crystal and the crystal structure of the phosphor is KBaPO4 with x=0, while the phosphor shows monoclinic crystal system and the crystal structure of the phosphor is NaBaPO4 when x≥0.6. The diffraction peak of X-ray diffraction （XRD） moves to the high-angle as increasing the mass fraction of x. The fluorescence spectra of NaxK1-xBa1-0.02PO4： 0.02Eu^2＋ show that the excitation spectra are broadband in the range of 210-400 nm with excitation peak of wavelength 270 nm and the emission spectra cover the broadband of 415-560 nm, and emission peaks of wavelength 443 nm are clearly observed, the emission intensity of NaxK1-xBa1-0.02PO4：0.02Eu^2＋ is the maximum when the mole ratio of Na^＋/K^＋ is 0.6/0.4; the empirical formula of Van Uitert is applied to calculate crystallography sites of Ba^2＋ replaced by Eu^2＋, the emission band centered at 441 nm originates from the Eu^2＋ center of the eight compounds, and the emission band centered at 471 nm originates from the Eu^2＋ center of the six compounds. The blue light-emitting phosphor Na0.6K0.4Ba1-x-0.02CaxPO4：0.02Eu^2＋ （x=0.00, 0.01, 0.03, 0.05, 0.07, 0.09, 0.11） are synthesized by the high-temperature solid- state method under the reducing atmosphere. The effects of Ca^2＋-doped and the spectral properties of the phosphors are investigated. The results show that the emission band of Na0.6K0.4Ba1-x-0.02CaxPO4：0.02Eu^2＋ covers a broadband of 415-475 nm, which originates from the 4f^65d^1-4f^75d^0 transition of Eu^2＋, and emission peaks of wavelength 443 nm is clearly observed, the emission intensity of Na0.6K0.4Ba1-x-0.02CaxPO4：0.02Eu^2~＋ is the maximum when x=0.07; The luminous intensity of thephosphors can be enhanced by both doping Ca^2＋ and changing the calcination temperature, but neither the crystal structure nor the shape of the emission spectrum of the phosphor has any changes.
出处
《激光与光电子学进展》
CSCD
北大核心
2016年第3期178-184,共7页
Laser & Optoelectronics Progress
基金
辽宁省教育厅科研项目(LS 2010119)
关键词
光谱学
发光性能
蓝色荧光粉
高温固相法
晶体学格位
spectroscopy
luminescence properties
blue phosphors
high-temperature solid-state method
crystallographic sites
