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Synthesis of Core-shell Lanthanide-doped Upconversion Nanocrystals for Cellular Applications
Published on: November 10, 2017
Synthesis of hexagonal-phase core-shell NaYF4 nanocrystals with tunable upconversion fluorescence
1Division of Bioengineering, Faculty of Engineering, National University of Singapore, Singapore.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 9, 2008
Summary
Researchers synthesized core-shell nanocrystals using a seeded growth method. These hexagonal-phase sodium yttrium fluoride (NaYF4) nanocrystals feature upconverting lanthanide ions, thulium (Tm) and erbium (Er), in distinct core and shell layers for advanced optical applications.
Area of Science:
- Materials Science
- Nanotechnology
- Inorganic Chemistry
Background:
- Core-shell nanostructures offer unique optical properties.
- Lanthanide-doped NaYF4 nanocrystals are known for their upconversion luminescence.
- Controlling dopant distribution in core-shell structures is crucial for optimizing performance.
Purpose of the Study:
- To synthesize hexagonal-phase core-shell NaYF4 nanocrystals with distinct dopant layers.
- To investigate the seeded growth approach for creating complex nanostructures.
- To enable tailored optical properties by controlling lanthanide ion placement.
Main Methods:
- Utilized a seeded growth approach starting with beta-NaYF4:Yb,Tm seed nanocrystals (20 nm diameter).
- Induced sequential growth of beta-NaYF4:Yb,Er and beta-NaYF4:Yb,Tm layers.
- Characterized the resulting core-shell nanostructures.
Main Results:
- Successfully synthesized hexagonal-phase core-shell-structured NaYF4:Yb,Tm@beta-NaYF4:Yb,Er and beta-NaYF4:Yb,Tm@beta-NaYF4:Yb,Er@beta-NaYF4:Yb,Tm nanocrystals.
- Demonstrated precise doping of thulium (Tm) in the core and erbium (Er) in the shell.
- The seeded growth method effectively controlled the formation of multi-layered core-shell architectures.
Conclusions:
- The seeded growth method is effective for fabricating complex core-shell nanocrystals.
- The synthesized NaYF4:Yb,Tm@NaYF4:Yb,Er core-shell nanocrystals offer a platform for tunable upconversion luminescence.
- This controlled doping strategy is promising for applications in photonics and bioimaging.
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