南京工业大学黄岭团队报道了正/负热膨胀核/壳NaYF₄:Yb/Ho@ScF₃纳米粒子中抑制多光子弛豫的抗热猝灭上转换发光。相关研究成果发表在2024年2月27日出版的《美国化学会杂志》。

热猝灭（TQ）被发现以来，它一直与发光纠缠在一起，而以多声子弛豫（MPR）为特征的晶格振动起着关键作用。考虑到MPR在外部压力下可能被抑制，研究人员设计了一种具有正/负热膨胀行为的α-NaYF₄:YbLn@ScF₃（Ln=Ho、Er和Tm）的核/壳上转换发光（UCL）系统，使得当加热时，芯的正热膨胀将受到外壳的负热膨胀的限制。

这种对芯晶格施加的压力抑制了MPR，减少了TQ消耗的能量，并最终节省了更多的发光能量，从而获得了抗TQ甚至热增强的UCL。

附：英文原文

Title: Antithermal Quenching Upconversion Luminescence via Suppressed Multiphonon Relaxation in Positive/Negative Thermal Expansion Core/Shell NaYF4:Yb/Ho@ScF3 Nanoparticles

Author: Yilin Wang, Jiahui Rui, Hao Song, Ze Yuan, Xiaoqiao Huang, Jingyao Liu, Jie Zhou, Ce Li, Hui Wang, Shuaihao Wu, Ran Chen, Mingdi Yang, Qilong Gao, Xiaoji Xie, Xianran Xing, Ling Huang

Issue&Volume: February 27, 2024

Abstract: Thermal quenching (TQ) has been naturally entangling with luminescence since its discovery, and lattice vibration, which is characterized as multiphonon relaxation (MPR), plays a critical role. Considering that MPR may be suppressed under exterior pressure, we have designed a core/shell upconversion luminescence (UCL) system of α-NaYF4:Yb/Ln@ScF3 (Ln = Ho, Er, and Tm) with positive/negative thermal expansion behavior so that positive thermal expansion of the core will be restrained by negative thermal expansion of the shell when heated. This imposed pressure on the crystal lattice of the core suppresses MPR, reduces the amount of energy depleted by TQ, and eventually saves more energy for luminescing, so that anti-TQ or even thermally enhanced UCL is obtained.

DOI: 10.1021/jacs.3c10886

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.3c10886