等离激元微纳腔实现镧系上转换发光单色和增强的研究

项目名称： 等离激元微纳腔实现镧系上转换发光单色和增强的研究

项目编号： No.11504307

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 李艾华

作者单位： 厦门大学

项目金额： 24万元

中文摘要： 上转换发光效率低、发光颜色难以调控是镧系掺杂纳米材料通往实用的两个瓶颈问题，而目前的材料工程很难将这两个问题统一起来用一种方法解决。我们提出利用等离激元微纳腔同时解决这两个问题的实验方案：以镧系上转换纳米晶（UCNCs）为对象，利用局域电场增强和 Purcell效应对上转换跃迁的增强和调控作用，实现镧系离子的增强单色上转换发光。本项目将设计并制备UCNC@SiO2@Ag核—壳结构亚微米球形腔，建立亚微米分辨单颗粒上转换荧光成像/光谱采集系统，选择性测试不同尺寸（腔模）的单个UCNC—微纳腔体系的上转换发光特性，观察微纳腔增强镧系离子上转换发光强度和调控其发光颜色的作用规律，利用相关理论，探索光子态密度调控上转换发光颜色和增强上转换发光强度的物理机制。此项研究不仅可以为等离激元光学优化镧系离子发光提供理论支撑，而且得到的增强单色上转换发光在高分辨全色显示、光伏电池等方面有重要应用潜力。

中文关键词： 镧系离子；上转换发光；等离激元微纳腔；光子态密度；光谱调制

英文摘要： Low efficiency and difficult tailoring the color of upconversion luminescence (UCL) are two bottlenecks for practical use of lanthanide-ion-actived nano-materials, however, it is hard to simultaneously solve both issues via a method of current material engineering. Thus, an experimental protocol based on plasmonic micro-/nano-cavity is proposed to solve both issues simultaneously by us, lanthanide-ions-doped nanocrystals (UCNCs) will be chose as object to investigate the influence of local field enhancement and Purcell effect on the enhancement of UCL intensity and regulation of UCL color, respectively, achieving enhanced single-band UCL of lanthanide ions. For this purpose, core-shell structured UCNC@SiO2@Ag spherical optical cavity with size of sub-micrometer will be designed and fabricated, a home-made single-particle UCL imaging/spectroscopic measurement system with sub-micrometer spatial resolution will be built, to selectively measure the UCL properties of a single UCNC-plasmonic micro-/nano-cavity hybrid system with different size (namely cavity mode), to observe the regularity of the influence of plasmonic micro-/nano-cavity on UCL enhancement and color modulation, lastly to explore the mechanism of photonic mode density on modulating the color and enhancing the intensity of UCL of lanthanide ions by using relevant basic theory. This study not only provides a theoretical basis for the use of plasmonics to optimize luminescence of lanthanide ions, but also the obtained enhanced single-band UCL possessing fascinating application potentials in high-spatial resolution full-color display, solar photovoltaic cell and so on.

英文关键词： lanthanide ions;upconversion luminescence;plasmonic micro-/nano-cavity;photonic mode density;spectral modulation