High-Brightness Red-Emitting Phosphor La₃(Si,Al)₆(O,N)₁₁:Ce³⁺ for Next-Generation Solid-State Light Sources

Area of Science:

• Materials Science
• Solid-State Lighting
• Luminescent Materials

Background:

• Laser-excited phosphor systems offer superior brightness compared to white LEDs for light sources.
• Red-emitting phosphors are crucial for high color-rendering index and low color-temperature white light.
• Existing red-emitting phosphors suffer from quantum efficiency quenching under high-power laser excitation, limiting their application.

Purpose of the Study:

• To develop a novel red-emitting phosphor with high brightness and tolerance to high-power laser excitation.
• To address the limitations of current red phosphors in laser-excited lighting applications.
• To investigate the potential of cerium (Ce³⁺)-doped materials for high-power excitation.

Main Methods:

• Synthesis of a novel phosphor, La₃(Si,Al)₆(O,N)₁₁:Ce³⁺ (LSA), through crystal-field modification of La₃Si₆N₁₁:Ce³⁺.
• Substitution of aluminum (Al) in silicon (Si) sites within the phosphor lattice.
• Evaluation of luminescent properties, including emission wavelength, high-power excitation tolerance, and thermal quenching.

Main Results:

• The synthesized LSA phosphor exhibits 640 nm red emission.
• LSA demonstrates tolerance to high-power laser excitation, a significant improvement over existing red phosphors.
• The material shows resistance to thermal quenching, indicating stability under demanding conditions.

Conclusions:

• La₃(Si,Al)₆(O,N)₁₁:Ce³⁺ (LSA) is a promising high-brightness red-emitting phosphor suitable for laser-excited light sources.
• The phosphor's ability to withstand high-power excitation and thermal stress overcomes critical limitations in current technology.
• LSA holds significant potential for industrial applications requiring ultrahigh brightness, such as advanced lighting and displays.