摘要
采用共沉淀法合成了Pb^(2+)掺杂CaMoO_(4)∶Dy^(3+),Eu^(3+)荧光粉,通过X射线衍射仪、荧光分光光度计对荧光粉的物相组成、发光特性以及激活离子间能量传递效率进行了表征及分析。结果表明,掺杂Pb^(2+)的CaMoO_(4)∶Dy^(3+),Eu^(3+)荧光粉样品没有出现新的衍射峰,说明Pb^(2+)很好地代替Ca^(2+)进入到晶格当中,CaMoO_(4)∶0.05Dy^(3+),0.15Eu^(3+),0.15Pb^(2+)荧光粉晶胞参数为a=b=0.5489 nm,c=1.2753 nm,Z=2,属于四方晶系,在391 nm波长激发下,484 nm处为Dy^(3+)(4F 9/2→6H_(15/2))的蓝光特征发射峰,575 nm处为Dy^(3+)(4F_(9/2)→6H_(13/2))跃迁产生的黄光发射峰,593 nm处为Eu^(3+)(5D 0→7F 1)跃迁产生的橙光发射峰,619 nm处为Eu^(3+)(5D_(0)→7F_(2))跃迁产生的红光发射峰。通过计算得出CaMoO_(4)∶Dy^(3+),Eu^(3+)荧光粉中Dy^(3+)和Eu^(3+)之间临界传递距离为1.5426 nm,能量传递机理是偶极-四极相互作用,能量传递效率接近60.31%,掺杂金属离子Pb^(2+)的荧光粉样品能量传递效率最高提升至72.40%。所以,掺杂Pb^(2+)能够大幅度提升Dy^(3+)与Eu^(3+)之间能量传递效率和改善荧光粉的发光性能,因此其在白光LED领域具有重要研究意义。
Pb^(2+)doped CaMoO_(4)∶Dy^(3+),Eu^(3+)phosphors were synthesized by coprecipitation method.The phase composition,luminescence characteristics and energy transfer efficiency between activated ions were characterized and analyzed by X-ray diffractometer and fluorescence spectrophotometer.The results show that the CaMoO_(4)∶Dy^(3+),Eu^(3+)doped with Pb^(2+)phosphor samples have no new diffraction peaks compared with the undoped phosphor samples.The above shows that Pb^(2+)is a good substitute for Ca^(2+)enters into the crystal lattice.The unit cell parameters are a=b=0.5489 nm,c=1.2753 nm,Z=2 belongs to the tetragonal crystal system for CaMoO_(4)∶0.05Dy^(3+),0.15Eu^(3+),0.15Pb^(2+)phosphor.Under the excitation of 391 nm wavelength,it can be seen that 484 nm blue light emission peak attributes to Dy^(3+)(4F_(9/2)→6H_(15/2)),575 nm is the yellow light emission peak produced by Dy^(3+)(4F_(9/2)→6H_(13/2))transition,593 nm is the orange light emission peak produced by Eu^(3+)(5D 0→7F_(1))transition,and 619 nm is the red light emission peak produced by Eu^(3+)(5D_(0)→7F_(2))transition.The critical transfer distance between Dy^(3+)and Eu^(3+)in CaMoO_(4)∶Dy^(3+),Eu^(3+)phosphors can be obtained by calculation,which is 1.5426 nm.The energy transfer mechanism is dipole-quadrupole interaction,the energy transfer efficiency is close to 60.31%,and the maximum sample energy transfer efficiency increases to 72.40%for Pb^(2+)doped phosphor.Therefore,it is concluded that doping with Pb^(2+)can greatly increase the energy transfer efficiency between Dy^(3+)and Eu^(3+)and improve the luminous performance of phosphors,so it has important research significance in the field of white LEDs.
作者
胡斌
郭亮
杨淑敏
曹丽萍
HU Bin;GUO Liang;YANG Shumin;CAO Liping(School of Physics and Electrical Engineering,Kashgar University,Kashgar 844006,China)
出处
《人工晶体学报》
CAS
北大核心
2021年第5期871-876,883,共7页
Journal of Synthetic Crystals
基金
喀什大学高层次人才科研启动经费项目(GCC18ZK-002)。
关键词
白光LED
钼酸盐
共沉淀法
稀土发光
能量传递
white LED
molybdate
coprecipitation method
rare earth luminescence
energy transfer
