A Mn⁴⁺-Doped Far-Red-Emitting Phosphor toward Full-Spectrum Lighting

Area of Science:

• Materials Science
• Solid-State Chemistry
• Luminescence

Background:

• Manganese-doped (Mn⁴⁺) oxide phosphors are crucial for full-spectrum and plant growth lighting.
• Developing efficient far-red emitting phosphors is essential for optimizing lighting technologies.

Purpose of the Study:

• To synthesize and characterize a novel far-red emitting CaLuAlO₄:Mn⁴⁺ phosphor.
• To evaluate its potential for full-spectrum lighting and plant growth applications.

Main Methods:

• High-temperature solid-phase synthesis method.
• Characterization of photoluminescence properties, including excitation and emission spectra.
• Measurement of internal quantum efficiency and absorptivity.
• Evaluation in packaged far-red light-emitting diodes (LEDs) for plant growth tests.

Main Results:

• Successfully synthesized CaLuAlO₄:Mn⁴⁺ phosphor exhibiting far-red emission at 707 nm under 365 nm excitation.
• Achieved an internal quantum efficiency of 55.04% and absorptivity of 81.48%.
• Demonstrated suitability for white light-emitting diodes (WLEDs) by achieving a low correlated color temperature (CCT = 3548 K) and high color rendering index (R_a = 96.5).
• Verified positive effects on plant growth in experiments.

Conclusions:

• CaLuAlO₄:Mn⁴⁺ is a promising far-red emitting phosphor for full-spectrum lighting and plant growth applications.
• The phosphor effectively compensates for far-red emission deficiencies in WLEDs.
• Its performance in plant growth experiments highlights its practical utility.