NaYF4∶Yb^3+,Ln^3+@NaYF4∶Yb^3+@NaYF4(Ln=Ho,Tm)核-双层壳纳米晶中Yb^3+调控的高效上转换发光  

Highly Enhanced Upconversion Luminescence Through Partially Isolate Yb3+in Core-shell-shell Structured NaYF4∶Yb3+,Ln3+@NaYF4∶Yb3+@NaYF4(Ln=Ho,Tm)Nanocrystals

作　　者：廖华珍 肖萍 叶松[1] 王德平[1] LIAO Hua-zhen;XIAO Ping;YE Song;WANG De-ping(School of Materials Science and Engineering,Tongji University,Shanghai 201804,China)

机构地区：[1]同济大学材料科学与工程学院,上海201804

出　　处：《发光学报》2020年第9期1102-1113,共12页Chinese Journal of Luminescence

基　　金：国家自然科学基金(51872200,51772210);上海市自然科学基金(18ZR1441900);国家重点研发计划(2018YFC1106302)资助项目。

摘　　要：采用共沉淀法合成了尺寸小于10 nm的Yb^3+/Ln^3+(Ln=Ho^3+,Tm^3+)掺杂β-NaYF4核纳米晶,在此基础上构建了NaYF4∶Yb^3+,Ln^3+@NaYF4∶Yb^3+@NaYF4核-双层壳结构纳米晶,并通过XRD和TEM测试证明了中间活性壳和最外层惰性壳的成功包覆。光谱结果表明,在活性核和活性壳中分别掺杂Yb^3+、并进一步生长最外层的惰性壳能够有效地提高Ho^3+和Tm^3+的上转换发射强度,这是由核-双层壳结构纳米晶对980 nm激发光的吸收增强以及Yb^3+浓度猝灭阈值的提高所引起的高效能量传递共同导致的。此外,通过调节中间壳层中的Yb^3+掺杂浓度,可以获得高效可调发光。本研究为开发多色高效上转换发光纳米晶提供了一条有效的途径。In this research,the Yb^3+/Ln^3+(Ln=Ho^3+and Tm^3+)dopedβ-NaYF4 core nanocrystals(NCs)with sub-10 nm size were synthesized with co-precipitation method,based on which the core-shell-shell structured NaYF4∶Yb^3+,Ln^3+@NaYF4∶Yb^3+@NaYF4 NCs were constructed.The successfully growth of the middle active-shell and the outmost inert-shell were proved by XRD and TEM measurements.The spectral results indicated that partially isolate Yb^3+dopant in active-core and active-shell and the growth of the outmost inert-shell can effectively improve the upconversion(UC)emission intensity of Ho^3+and Tm^3+,which is resulted from the enhanced absorption of 980 nm excitation light and energy transfer efficiency ascribing to the increased Yb^3+concentration quenching threshold.Moreover,through adjusting Yb^3+doping concentration in the middle-shell,the tunable emission can be obtained.This research suggested a general route for the development of highly-efficient luminescent upconversion nanocrystals(UCNCs)in a broad color range.

关 键 词：上转换发光 核-双层壳结构 β-NaYF4 

分 类 号：O482.31[理学—固体物理]