Lighting the future: high-stability bluish-green phosphors for advanced LEDs

Warm white light-emitting diodes (WLEDs) are essential for modern lighting due to their energy efficiency, long lifespan, and environmental benefits. However, the performance of traditional phosphors in LEDs often degrades under prolonged thermal stress, leading to colour shifts and reduced brightness. In response, researchers have turned to remote phosphor technology to address these issues.

A research team from SASTRA Deemed University, led by Dr. Sakthivel Gandhi, developed a bluish-green emitting phosphor using silica nanoparticles instead of conventional precursors. This new method achieved a more homogeneous distribution of dopants, enhancing luminescence and resulting in a 48% increase in emission intensity compared to traditional methods.

The new phosphor exhibits significant thermal stability, maintaining 56% of its luminescence intensity at 190 °C, which is important for its use in high-power LEDs. To improve its performance, a flexible remote phosphor film was developed with an optimized phosphor-to-resin ratio to enhance emission efficiency and stability under different voltage conditions. Although the distance helps protect the phosphor film from heat, if the phosphor is affected, the film can be replaced without impacting the lifespan of the LEDs.

This breakthrough could result in brighter, more stable, and energy-efficient LED lights for homes, offices, and streets. It is like giving light bulbs a superpower to shine better, even under increased temperatures.

The work entitled “Silica nanoparticles assisted Ba₂SiO₄:Eu²⁺—a bluish-green emitting remote phosphor for white light application” was published on Frontiers of Optoelectronics (published on April 9, 2025).