Researchers have built an LED so thin it could one day be applied to walls like wallpaper. Despite its size, the prototype produces a bright, warm light that closely mimics the sun’s natural glow.
The team behind the breakthrough, led by Xianghua Wang and colleagues, wanted to tackle a familiar problem in artificial lighting: harsh, narrow-spectrum LEDs that can strain the eyes and distort color. Their solution was to use quantum dots, nanoscale crystals that emit light in precise wavelengths. By blending red, yellow-green, and blue quantum dots, they created a material that produces a continuous spectrum similar to sunlight.
To stabilize each color, the researchers coated the quantum dots with multiple zinc sulfide layers before layering them with conductive polymers and transparent electrodes. The result is a light-emitting stack just tens of nanometers thick, capable of glowing evenly under low voltage.
When powered at around 11.5 volts, the device emitted a soft white light with reduced blue intensity and enhanced red, making it gentler on human eyes. The prototype also achieved a Color Rendering Index (CRI) above 92 percent, meaning it can reproduce colors more accurately than most commercial LEDs.
In further testing, 26 versions of the device were built with different conductive materials. Many reached full brightness at just 8 volts, and most exceeded the brightness levels used in computer displays.
Beyond performance, the technology’s flexibility opens possibilities for new types of lighting and display applications. The thin structure could be applied to curved surfaces or embedded into lightweight panels, turning ceilings, windows, or walls into uniform light sources.
While more work is needed to improve efficiency and long-term stability, the researchers believe their design brings them closer to artificial light that feels natural. In the future, LEDs that mimic daylight could help reduce eye fatigue, improve sleep cycles, and transform how we illuminate indoor spaces.
Original Story: A prototype LED as thin as wallpaper — that glows like the sun – American Chemical Society
