Journal Article10.1021/NL300421N
Direct Imaging the Upconversion Nanocrystal Core/Shell Structure at the Subnanometer Level: Shell Thickness Dependence in Upconverting Optical Properties
Fan Zhang,Renchao Che,Xiaomin Li,Chi Yao,Jianping Yang,Dengke Shen,Pan Hu,Wei Li,Dongyuan Zhao +8 more
299
TL;DR: During the epitaxial growth of the NaGdF(4) shell layer by layer, surface defects of the nanocrystals can be gradually passivated by the homogeneous shell deposition process, which results in the obvious enhancement in overall UC emission intensity and lifetime and is more resistant to quenching by water molecules.
read more
Abstract: Lanthanide-doped upconversion nanoparticles have shown considerable promise in solid-state lasers, three-dimensional flat-panel displays, and solar cells and especially biological labeling and imaging. It has been demonstrated extensively that the epitaxial coating of upconversion (UC) core crystals with a lattice-matched shell can passivate the core and enhance the overall upconversion emission intensity of the materials. However, there are few papers that report a precise link between the shell thickness of core/shell nanoparticles and their optical properties. This is mainly because rare earth fluoride upconversion core/shell structures have only been inferred from indirect measurements to date. Herein, a reproducible method to grow a hexagonal NaGdF4 shell on NaYF4:Yb,Er nanocrystals with monolayer control thickness is demonstrated for the first time. On the basis of the cryo-transmission electron microscopy, rigorous electron energy loss spectroscopy, and high-angle annular dark-field investigations ...
read more
Chat with Paper
AI Agents for this Paper
Find similar papers on Google Scholar, PubMed and Arxiv
Write a critical review of this paper
Analyze citations of this paper to find unaddressed research gaps
Citations
Upconversion Nanoparticles: Design, Nanochemistry, and Applications in Theranostics
TL;DR: Applications in Theranostics Guanying Chen,*,†,‡ Hailong Qiu,*,‡ and Xiaoyuan Chen.
2.3K
Controlling upconversion nanocrystals for emerging applications
TL;DR: This work highlights the advances in functionalization strategies that enable the broad utility of upconversion nanocrystals for multimodal imaging, cancer therapy, volumetric displays and photonics.
1.3K
Energy transfer in lanthanide upconversion studies for extended optical applications
TL;DR: A fundamental understanding of energy transfer in lanthanide-supported photon upconversion is presented and the emerging progress in excitation selection based on the energy transfer within lanthanides ions or activation from antennae is introduced.
958
References
Upconversion and Anti-Stokes Processes with f and d Ions in Solids
TL;DR: Before the 1960s, all anti-Stokes emissions, which were known to exist, involved emission energies in excess of excitation energies by only a few kT and were linked to thermal population of energy states above excitation states by such an energy amount.
4.7K
In Vivo Imaging of Quantum Dots Encapsulated in Phospholipid Micelles
Benoit Dubertret,Paris A. Skourides,David J. Norris,David J. Norris,Vincent Noireaux,Ali H. Brivanlou,Albert Libchaber +6 more
TL;DR: C encapsulated individual nanocrystals in phospholipid block–copolymer micelles acted as in vitro fluorescent probes to hybridize to specific complementary sequences and were followed to the tadpole stage, allowing lineage-tracing experiments in embryogenesis.
3.2K
Simultaneous phase and size control of upconversion nanocrystals through lanthanide doping
Feng Wang,Yu Han,C. S. Lim,Yunhao Lu,Juan Wang,Jun Xu,Hongyu Chen,Chun Zhang,Minghui Hong,Minghui Hong,Xiaogang Liu +10 more
TL;DR: The results suggest that the doping-induced structural and size transition, demonstrated here in NaYF4 upconversion nanocrystals, could be extended to other lanthanide-doped nanocrystal systems for applications ranging from luminescent biological labels to volumetric three-dimensional displays.
3.1K
Recent advances in the chemistry of lanthanide-doped upconversion nanocrystals
Feng Wang,Xiaogang Liu +1 more
TL;DR: This tutorial review focuses on the recent development of various synthetic approaches and possibilities for chemical tuning of upconversion properties, as well as giving an overview of biological applications of these luminescent nanocrystals.
2.8K
Lanthanide Luminescence for Biomedical Analyses and Imaging
TL;DR: This data indicates that the prostate-Specific antigen in the europium-Tetracycline complex acts as a ‘spatially aggregating force’ to form terbium complexes in the Optical Probes.
2.4K