Quantum Cutting in KGd(CO3)2:Tb3+ Green Phosphor
Dechuan Li1,2, Jian Qian1,2, Lei Huang1,2
1School of Physics and Electronic Information, Huaibei Normal University, Huaibei 235000, China.
Nanomaterials (Basel, Switzerland)
|January 21, 2023
Summary
New quantum cutting phosphors, KGd(CO3)2:Tb3+, were synthesized for efficient energy conversion. These materials demonstrate high quantum yields, making them suitable for ultraviolet-excited solid-state lighting applications.
Area of Science:
- Materials Science
- Solid-State Lighting
- Luminescence
Background:
- Longer excitation wavelengths in phosphors correlate with higher energy conversion efficiency.
- Quantum cutting phosphors offer enhanced efficiency by utilizing high-energy photons to generate multiple lower-energy photons.
Purpose of the Study:
- To synthesize and characterize quantum cutting KGd(CO3)2:Tb3+ phosphors.
- To investigate the potential of these phosphors for efficient energy conversion under middle-wave ultraviolet excitation.
Main Methods:
- Hydrothermal synthesis method used for KGd(CO3)2:Tb3+ phosphor preparation.
- Structural analysis confirmed monoclinic structures across a wide Tb3+ doping range.
- Photoluminescence spectroscopy employed to study excitation and emission properties.
Main Results:
- Efficient quantum cutting was achieved via energy transfer from Gd3+ sensitizing levels (6D3/2 and 6I17/2) to Tb3+.
- Maximum quantum yields reached 163.5%, 119%, and 143% at excitation wavelengths of 244 nm, 273 nm, and 283 nm, respectively.
- A continuous and efficient excitation band from 273-283 nm was observed, aligning with commercial 275 nm LED chips.
Conclusions:
- KGd(CO3)2:Tb3+ phosphors exhibit efficient green emission suitable for ultraviolet-excited solid-state light sources.
- The observed excitation bands and high quantum yields indicate significant potential for advanced lighting applications.
- The material's properties suggest it can expand the utility of current solid-state lighting technologies.
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