湿热环境下LED荧光粉的性能退化规律及机理研究  

Degradation Mechanism Analysis for LED Phosphors under Hygrothermal Environment

作　　者：樊嘉杰[1,2] 王珍 罗潇 周玲 樊学军 张国旗[4] Fan Jiajie;Wang Zhen;Luo Xiao;Zhou Ling;Fan Xuejun;Zhang Guoqi(Hohai University,Changzhou 213022,China;Changzhou Institute of Technology Research for Solid State Lighting,Changzhou 213161,China;Lamar University,Beaumont,TX 77710,USA;Delft University of Technology,Delft 2628,the Netherlands)

机构地区：[1]河海大学机电工程学院,江苏常州213022 [2]常州市武进区半导体照明应用技术研究院,江苏常州213161 [3]美国拉玛尔大学,德克萨斯博蒙特77710 [4]荷兰代尔夫特理工大学,代尔夫特2628 [5]河海大学,江苏常州213022

出　　处：《稀有金属材料与工程》2020年第1期153-160,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51805147,61673037);江苏省六大人才高峰项目(GDZB-017);中央高校基本科研业务费专项资金(2017B15014)。

摘　　要：选用制备高品质白光LED所常用黄、红、橙3种荧光粉,研究其在高温高湿老化试验和浸水模拟饱和水环境实验中的发光性能、发热性能、晶体结构和微观颗粒形貌变化规律,分析不同荧光粉的性能退化机理。结果表明:(1)在湿热环境下荧光粉易与水发生反应产生OH-,提升湿环境pH值,引起主体晶体结构结晶度下降,晶格振动增强,光致发热能量增加,诱发热猝灭效应;同时荧光粉表面粗化效应增加蓝光散射,降低蓝光吸收和转化效率;(2)在浸水模拟实验的饱和水环境中,荧光粉的发光性能和发热性能变化规律与高温高湿长期老化试验结果一致,可以有效评估LED荧光粉在湿热环境下可靠性。This study selects yellow,red and orange phosphors used in high color rendering white packages,analyzes their luminescence and thermal properties,crystal structures and micro morphologies during both the high temperature and high moisture ageing test and the water immersion test,and finally figures out the degradation mechanisms of different phosphors.The results show that:1)the hydrolysis reaction of phosphors under hygrothermal environment produces OH-and increases the environment’s pH value,which can lower the crystallinity of phosphor hosts,increase the lattice vibration and light-induced heat,and enhance the thermal quenching effect of phosphors.Meanwhile,the surface roughening of phosphor particles can increase the blue light scattering and lower its absorption and conversion efficiency;2)the degradation trends of both luminescence and thermal properties of phosphors under the water immersion test are similar to those under high temperature and high moisture ageing test.So it is an effective method to assess the reliability of LED phosphors under hygrothermal environment.

关 键 词：白光LED 荧光粉 高温高湿 浸水模拟实验 失效机理 

分 类 号：O482.91[理学—固体物理]