摘要
以乙二醇为溶剂,采用低温溶剂热法制备了Ho3+/Yb3+共掺杂In2O3纳米晶。利用X射线晶体衍射(XRD)、透射电子显微镜(TEM)对粒子的结构和形貌进行表征,结果表明,合成的样品为纯的立方相In2O3,颗粒尺寸约为30 nm。通过上转换发光(UCL)光谱研究了粒子的上转换发光性质,在980 nm半导体激光激发下,In2O3∶Ho3+,Yb3+纳米晶发射出强的绿色和弱的红色上转换发光,分别归属于Ho3+离子(5F4,5S2)→5I8和5F5→5I8跃迁。研究了不同Ho3+和Yb3+离子掺杂浓度对上转换发光性能的影响,确定了Ho3+和Yb3+最佳掺杂摩尔分数分别为3%和4%。双对数曲线显示,绿光和红光的发射过程均为双光子吸收过程。对样品的上转换发光机制进行了初步讨论。
In2O3∶Ho3＋,Yb3＋ nanocrystals with efficient upconversion luminescence were prepared by solvent thermal method using glycol as solvent.The samples were characterized by X-ray diffraction（XRD）,transmission electron microscopy（TEM）,diffuse reflectance spectra,and upconversion luminescence spectra.XRD results indicate that the products are cubic phase.TEM images show that the In2O3∶Ho3＋,Yb3＋ nanoparticles are sphere shape with an average size of 30 nm.The diffuse reflectance spectra give four narrow bands at 448,538,644 and 975 nm,corresponding to the 5I8→5G6（448 nm）,5I8→5S2/5F4（538 nm）,5I8→5F5（644 nm） transitions of Ho3＋ ions and 2F7/2→2F5/2（975 nm） transition of Yb3＋ ions.Under the excitation of 980 nm,In2O3∶Ho3＋,Yb3＋ nanocrystals can emit strong green emission and weak red emission,corresponding to（5F4,5S2）→5I8,5F5→5I8 transitions of Ho3＋.Upconversion luminescence of In2O3∶Ho3＋,Yb3＋ nanocrystals codoped with different concentrations of Ho3＋ and Yb3＋ ions were investigated to improve the luminescene intensity.The results show that the strongest upconversion emission can be achieved at a Ho3＋ mole fraction of 3% and an Yb3＋ mole fraction of 4%.The lnI-lnP curves show that both the green and red emissions are double-photon process and the possible mechanism is proposed.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2011年第7期655-659,共5页
Chinese Journal of Luminescence
基金
国家自然科学基金(30670523)
中央高校基本科研业务费专项基金资助项目
作者简介
邹少瑜（1985-），女，广东肇庆人，主要从事功能材料的研究。
通讯联系人；E—mail：tmjx@jnil．edu．cn，Tel：（020）85220223
