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Updated: Feb 12, 2026

An Integrated System to Remotely Trigger Intracellular Signal Transduction by Upconversion Nanoparticle-mediated Kinase Photoactivation
Published on: August 30, 2017
Direct Identification of Surface Defects and Their Influence on the Optical Characteristics of Upconversion
Wenjuan Bian1,2, Yue Lin3, Ting Wang4
1Faculty of Materials Science and Engineering , Kunming University of Science and Technology , Kunming , Yunnan Province 650093 , People's Republic of China.
Abstract:
Core-shell structure is an obvious concept to suppress surface-related deactivations in lanthanide-doped upconversion nanoparticles (UCNPs). However, no direct observation of atomic-scale surface restoration, which can improve the upconversion photoluminescence, has been reported. Here, we use aberration-corrected high-angle annular dark field scanning transmission electron microscopy to study the surface condition of KLu2F7:Yb3+,Er3+ bare core UCNPs. Due to the very thin and uniform thickness of the UCNPs, we observe unambiguously that the recovery from surface defects enhances upconversion photoluminescence. Furthermore, the realization of dominant green lasing emission under pulsed laser excitation confirms the high crystallinity of the UCNPs.
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