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Ni2+ in Distorted Octahedral Geometry toward High-Efficiency NIR-II/III emitter
Ye Yang1, Shanli Qin1,2, Junfang Zhang1
1School of Chemistry and Chemical Engineering, State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, Guangxi Key Laboratory of Electrochemical Energy Materials, Guangxi Colleges and Universities Key Laboratory of Applied Chemistry Technology and Resource Development., Guangxi University, Nanning, 530004, China.
This study enhances near-infrared (NIR) II-III phosphors by distorting crystallographic sites, achieving a record external quantum yield (EQY) of 9.00%. This breakthrough improves NIR phosphor efficiency for advanced applications.
Area of Science:
- Materials Science
- Solid State Chemistry
- Luminescence
Background:
- Nickel-activated (Ni2+) phosphors emit in the near-infrared (NIR) II-III region, but suffer from low external quantum yields (EQYs), typically below 8%.
- Low EQY limits the practical applications of these promising NIR-emitting materials.
Purpose of the Study:
- To enhance the EQY of Ni2+-activated phosphors for improved NIR emission.
- To investigate the effect of crystallographic site distortion on phosphor performance.
Main Methods:
- A distortion of crystallographic site strategy was employed.
- LaTiTaO6:0.004Ni2+ was synthesized and characterized.
- The distortion degree of octahedral geometry was analyzed.
- Absorption efficiency and EQY were measured.
Main Results:
- LaTiTaO6:0.004Ni2+ achieved an EQY of ~9.00% at 1450 nm, the highest reported for Ni2+ single-doped phosphors.
- Crystallographic site distortion increased from 0.038 to 0.047, enhancing absorption efficiency to 38.6% by breaking parity-forbidden d-d transitions.
- The material demonstrated potential in spectral analysis when mixed with LaTiTaO6:0.04Cr3+.
Conclusions:
- Crystallographic site distortion is an effective strategy for boosting EQY in Ni2+-doped phosphors.
- This work presents a novel approach for developing highly efficient NIR-II to NIR-III phosphors.
- The findings pave the way for advanced applications requiring efficient NIR emission.
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