A manufacturing technology has emerged that can boost the performance of perovskite light-emitting diodes (PeLEDs), which are drawing attention as next-generation display materials.
A joint team from Seoul National University and the University of Cambridge said it developed PeLEDs with improved efficiency and color purity by controlling perovskite crystals to grow uniformly even in the vacuum deposition process used for conventional organic light-emitting diode (OLED) production. The results were published on Jan. 1 in the journal Nature Nanotechnology.
Perovskite has drawn interest as a display material beyond OLED because it can produce bright, vivid light. A particular advantage is that it can be made by vacuum deposition, which vaporizes materials in a vacuum and coats them as a thin film on a substrate. Because this method is widely used in current OLED production, it has strong potential to be used with existing equipment through consolidation.
The problem was that perovskite crystallized too quickly and unevenly during deposition. When multiple crystal structures are mixed, light-emission efficiency drops and color can become dull. Simply put, to make a good image, the material must grow uniformly, but with existing methods it was difficult to finely control that process.
To solve this, the researchers introduced an organic molecule called an "X-type spacer." During perovskite formation, this molecule prevents crystals from growing disorderly and helps selectively form structures favorable for light emission. The team also developed a "hetero scaffold" by combining it with lithium fluoride. This serves as a kind of seeding layer that helps crystals grow evenly.
As a result, the team fabricated thin films with photoluminescence efficiency above 85% and achieved an external quantum efficiency of 21.9% in PeLEDs using them. External quantum efficiency indicates how efficiently an LED converts electricity into light. The emission linewidth was 16.8 nm (nanometers, one-billionth of a meter). Emission linewidth indicates how narrowly and cleanly the light's color converges; the smaller the value, the crisper the color. The researchers confirmed that the developed PeLEDs can also be implemented on large-area substrates, flexible substrates, and patterned structures.
Professor Lee Tae-woo said, "With a vacuum deposition process compatible with existing OLED production infrastructure, we achieved perovskite light-emitting devices with world-class efficiency and color purity. This will serve as a key enabling technology that accelerates the practical use of ultra-high-resolution displays and AR/VR microdisplays."
References
Nature Nanotechnology (2026), DOI: https://doi.org/10.1038/s41565-026-02208-y