【作者】 陈岩； 王静； 张信果； 张功国； 龚孟廉； 苏锵；

【Author】 Yan Chen Jing Wang~* Xinguo Zhang Gongguo Zhang Menglian Gong Qiang Su (Ministry of Education Key Laboratory of Bioinorganic and Synthetic Chemistry,State Key Laboratory of Optoelectronic Materials and Technologies,School of Chemistry and Chemical Engineering,Sun Yat-sen University,Guangzhou,Guangdong 510275,P.R.China.)

【机构】 生物无机与合成教育部重点实验室光电材料与技术国家重点实验室,中山大学化学与化学工程学院；

【摘要】 本文采用高温固相法合成了一种新的绿光发射荧光粉LiSrPO₄:Eu²⁺,Tb³⁺。通过激发与发射光谱、荧光衰减、浓度淬灭等方法系统研究了其发光性质,并进行了绿色LED器件的封装。结果显示:在LiSrPO₄基质中实现了Eu²⁺到Tb³⁺的能量传递,得到了Tb³⁺离子的绿光发射。通过对荧光衰减曲线拟合计算得到最大传递效率是66.4%。由激发光谱可以观察到Eu²⁺在280-410nm有强的吸收带,这与近紫外芯片（350～420 nm）非常匹配,说明此荧光粉适合近紫外芯片激发。同时,结合370nm的芯片做了器件封装,结果显示,通过Eu²⁺强的宽带吸收,把能量传递给Tb³⁺离子,实现了Tb³⁺离子的绿光发射。从而改善了Tb³⁺作为发光中心时吸收较弱的缺点,拓展了Tb³⁺离子在LED领域的应用。更多还原

【Abstract】 An intense green phosphor,LiSrPO₄:Eu²⁺,Tb³⁺,was synthesized by high temperature solid-state reaction.The photoluminescence excitation and emission spectra,the lifetime and concentration effect are investigated in detail.The results show that an efficient non-radiative energy transfer from Eu²⁺ to Tb³⁺ occurs and its efficiency is about 66.4%.Tb³⁺ ions give an intense green emitting light by a strong excitation band of Eu²⁺ ions at 280-410nm,matching well with the dominant emission band of（n）-UV（350～420 nm） LEDs.A phosphor converted green LED was fabricated by coating the LiSrPO₄:Eu²⁺,Tb³⁺ phosphor onto（n）-UV chip emitting at 370 nm.These results demonstrate that Tb³⁺ ion with low 4f-4f absorption efficiency in（n）-UV region can play a role of activator in narrow green emitting phosphor potentially useful in（n）-UV GaN-based LED through efficient energy feeding by allowed 4f-5d absorption of Eu²⁺ with high oscillator strength.更多还原