A novel red phosphor Ca₂ YNbO₆ :Eu³⁺ for WLEDs

Area of Science:

• Materials Science
• Solid-State Chemistry
• Luminescence

Background:

• Double perovskite compounds offer desirable physicochemical, thermal, and optical properties.
• Developing efficient red phosphors is crucial for advanced lighting applications, particularly white light-emitting diodes (WLEDs).

Purpose of the Study:

• To synthesize and characterize a novel red phosphor based on the Ca2YNbO6:xEu3+ double perovskite system.
• To evaluate its photoluminescence, thermal stability, and chromaticity for potential use in WLEDs.

Main Methods:

• High-temperature solid-phase synthesis method.
• Comprehensive characterization including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), absorption, photoluminescence, and thermal analysis.
• Evaluation of Commission Internationale de l'éclairage (CIE) chromaticity coordinates.

Main Results:

• Phase-pure Ca2YNbO6:xEu3+ samples were successfully synthesized with uniform morphology and elemental distribution.
• Optimal luminescence intensity was achieved at a Eu3+ doping concentration of 0.4, emitting red light at 612 nm.
• The phosphor demonstrated superior thermal stability, retaining 75% of its room-temperature luminescence intensity at 425 K.
• The CIE chromaticity coordinates were close to the National Television Standards Committee standard, indicating high color purity (99.90%) and a low correlated color temperature (2656 K).

Conclusions:

• Ca2YNbO6:0.4Eu3+ exhibits excellent luminescent properties, superior thermal stability, and ideal chromaticity for red phosphor applications.
• This novel double perovskite phosphor is a viable candidate to replace existing red phosphors in WLEDs.