CaLu2Sc2Al2SiO12:Ce3+ Green Phosphors for High-Quality White LEDs
Xiaoyuan Chen1, Xiaoyong Huang1
1College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024, P.R. China.
Inorganic Chemistry
|January 29, 2025
Summary
A new broadband green-emitting phosphor, CaLu2Sc2Al2SiO12:Ce3+ (CLSASO:Ce3+), offers improved efficiency and bandwidth for warm-white LEDs. This novel material enhances color rendering and luminous efficiency in solid-state lighting applications.
Area of Science:
- Materials Science
- Solid-State Lighting
- Luminescence
Background:
- Broadband green phosphors are crucial for high-color-rendering warm-white LEDs.
- Existing green phosphors often suffer from limited emission bandwidth and low quantum efficiency.
- Developing efficient green phosphors is key for advanced solid-state lighting.
Purpose of the Study:
- To synthesize and characterize a novel broadband green-emitting garnet phosphor, CaLu2Sc2Al2SiO12:Ce3+ (CLSASO:Ce3+).
- To evaluate its performance for warm-white LED applications, focusing on emission bandwidth, quantum efficiency, thermal stability, and color properties.
- To demonstrate the potential of CLSASO:Ce3+ in a prototype LED device.
Main Methods:
- Synthesis of CLSASO:Ce3+ phosphor via a solid-state reaction method.
- Photoluminescence spectroscopy to analyze emission spectra, bandwidth (fwhm), and quantum efficiency.
- Temperature-dependent emission measurements to assess thermal stability.
- Fabrication and testing of a prototype warm-white LED device incorporating the phosphor.
Main Results:
- The synthesized CLSASO:3%Ce3+ exhibits broadband green emission centered at 534 nm with a large fwhm of 114 nm, surpassing commercial LuAG:Ce3+.
- Achieved internal/external quantum efficiencies of 78.3%/50.1% with desirable CIE color coordinates (0.3462, 0.5496).
- Demonstrated excellent thermal stability (retaining 46% intensity at 423 K) and color stability.
- A prototype LED device using CLSASO:3%Ce3+ achieved a high color rendering index (Ra = 90.2), color temperature of 4047 K, and luminous efficiency of 65.6 lm W-1.
Conclusions:
- CLSASO:Ce3+ is a highly efficient broadband green-emitting phosphor suitable for high-performance warm-white LEDs.
- Its superior spectral properties and thermal stability make it a promising alternative to existing phosphors.
- This development contributes to the advancement of healthy and high-quality solid-state lighting solutions.
