Superenhancement Photon Upconversion Nanoparticles for Photoactivated Nanocryometer

作者：Qiqing Li, Xiaoyu Xie, Han Wu, Hao Chen, Wang Wang, Xianggui Kong, Yulei Chang · 发表于：Nano Letters · 年份：2023 · DOI：10.1021/acs.nanolett.3c00495 · 被引用次数：52 · 研究领域：Luminescence Properties of Advanced Materials、Luminescence and Fluorescent Materials、Nanoplatforms for cancer theranostics

Highly doped lanthanide luminescent nanoparticles exhibit unique optical properties, providing exciting opportunities for many ground-breaking applications, such as super-resolution microscopy, deep-tissue bioimaging, confidentiality, and anticounterfeiting. However, the concentration-quenching effect compromises their luminescence efficiency/brightness, hindering their wide range of applications. Herein, we developed a low-temperature suppression cross-relaxation strategy, which drastically enhanced upconversion luminescence (up to 2150-fold of green emission) in Er 3+ -rich nanosystems. The cryogenic field opens the energy transport channel of Er 3+ multiphoton upconversion by further suppressing phonon-assisted cross-relaxation. Our results provide direct evidence for understanding the energy loss mechanism of photon upconversion, deepening a fundamental understanding of the upconversion process in highly doped nanosystems. Furthermore, it also suggests the potential applications of upconversion nanoparticles for extreme ambient-temperature detection and anticounterfeiting.