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Triplet Fusion Upconversion Nanocapsule Synthesis
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UVC upconversion material under sunlight excitation: LiYF(4): Pr(3+).
Optics Letters
|February 13, 2016
Summary
Ultraviolet-C (UVC) upconversion emission was observed in a Pr3+-doped lithium yttrium fluoride microcrystal. Two-photon processes are crucial for UVC upconversion emission under both laser and sunlight excitation.
Area of Science:
- Solid-state spectroscopy
- Materials science
- Photophysics
Background:
- Upconversion luminescence is a process where lower energy photons are converted into higher energy photons.
- Lithium yttrium fluoride (LiYF4) doped with trivalent praseodymium (Pr3+) ions is a promising material for luminescence applications.
- Ultraviolet-C (UVC) emission is of interest for various applications, including sterilization and photolithography.
Purpose of the Study:
- To investigate ultraviolet-C (UVC) upconversion emission in LiYF4:Pr3+ microcrystals.
- To explore the excitation density dependence of UVC upconversion emission under both laser and sunlight.
- To elucidate the underlying mechanisms of UVC upconversion emission in this material.
Main Methods:
- Synthesis of LiYF4:Pr3+ microcrystals.
- Optical spectroscopy measurements under controlled excitation conditions.
- Analysis of excitation density dependence to identify luminescence mechanisms.
Main Results:
- Observation of UVC upconversion emission in LiYF4:Pr3+ microcrystals under sunlight excitation.
- Demonstration that two-photon processes significantly contribute to the UVC upconversion emission intensity.
- Correlation between excitation density and emission intensity under both laser and sunlight.
Conclusions:
- Two-photon absorption processes are a key mechanism for achieving UVC upconversion emission in LiYF4:Pr3+.
- Sunlight can be effectively utilized as an excitation source for UVC upconversion.
- The observed UVC emission under sunlight excitation holds significant potential for practical applications.
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