State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China.
Nanoscale. 2017 Jun 14;9(23):7941-7946. doi: 10.1039/c7nr01403a.
It is generally accepted that a lanthanide ions based upconversion material follows an activator low doping strategy (normally <3 mol%), because of the restriction of the harmful concentration quenching effect. Here, we demonstrate that this limitation can be broken in nanostructures. Simply by using an inert shell coating strategy, the concentration quenching effect for the activator (Er) could be eliminated and highly efficient upconversion luminescence realized in the activator fully doped nanostructure, e.g. NaErF@NaYF. More importantly, this novel nanostructure achieves some long-cherished desires, such as multiple-band co-excitation (∼800 nm, ∼980 nm and ∼1530 nm) and monochromic red emission. Proof-of-concept experiments are presented of the potential benefit of this structure in solar cells and anti-counterfeiting. This nanostructure offers new possibilities in realizing high upconversion emission and novel functionalities of lanthanide based nanomaterials.
人们普遍认为，镧系离子上转换材料遵循激活剂低掺杂策略（通常<3mol%），因为受到有害的浓度猝灭效应的限制。在这里，我们证明这种限制可以在纳米结构中被打破。通过简单地使用惰性壳层包覆策略，即可消除激活剂（Er）的浓度猝灭效应，并在激活剂完全掺杂的纳米结构中实现高效的上转换发光，例如 NaErF@NaYF。更重要的是，这种新型纳米结构实现了一些长期以来的期望，例如多波段共激发（∼800nm、∼980nm 和∼1530nm）和单色红光发射。我们提出了该结构在太阳能电池和防伪方面的潜在应用的验证实验。这种纳米结构为实现基于镧系元素的纳米材料的高上转换发射和新颖功能提供了新的可能性。
