In a recent study led by Professor Konstantinos Daskalakis at the University of Turku in Finland, researchers have developed a new type of white organic light-emitting diode (OLED) that operates using a single emitter. The work, presents a streamlined approach to creating efficient and sustainable lighting technology that could simplify manufacturing and reduce reliance on scarce materials.
Kumar, M., Dutta, A., Qureshi, H. A., Papachatzakis, M. A., Abdelmagid, A. G., & Daskalakis, K. S. (2025). Single‐Emitter White OLEDs via Microcavity Spectral Engineering. Advanced Optical Materials, 13(28). https://doi.org/10.1002/adom.202501358
White OLEDs are used in premium displays, architectural lighting, and advanced design applications. Traditional versions rely on complex stacks of organic materials combined with red, green, and blue dopants—many of which contain heavy metals. They also typically use a transparent electrode made of indium tin oxide, a costly material with limited global supply. While effective, this structure increases production complexity, material waste, and environmental impact.
Professor Daskalakis and his team, including Dr. Manish Kumar, took a different approach. Instead of blending multiple emitters, they engineered a system that produces white light using only one metal-free blue emitter, known as DMAC-DPS. The researchers achieved this by embedding the material in a finely tuned optical cavity made entirely from aluminum, where both mirrors act as electrodes.
By adjusting the thickness of the cavity and leveraging surface plasmon polaritons—electromagnetic ripples that travel along the metal’s surface—the researchers were able to control how the emitted light interacts within the structure. This interaction broadens the color spectrum, effectively converting blue emission into tunable white light without any additional dopants or complex layering.
The new OLED is top-emitting, meaning light is emitted through the top electrode rather than the substrate. This configuration eliminates the need for transparent conductive materials like indium tin oxide. The result is a much simpler stack that uses materials already familiar to OLED manufacturers, making the design compatible with existing production systems.
The research team reported that the new OLED can produce light ranging from warm white, around 3,790 K, to cool white, about 5,050 K. This tunability is achieved purely through physical structuring, not chemical mixing. The team’s results highlight how optical engineering can replace chemical complexity, a significant step toward making OLED lighting both more sustainable and easier to produce at scale.
From an engineering standpoint, the significance of this breakthrough lies in its simplicity. By removing heavy-metal dopants and avoiding indium tin oxide, the researchers have reduced the environmental footprint of OLED manufacturing. This approach could lead to lower material costs, simpler assembly processes, and improved recyclability. It also opens up design opportunities for reflective and flexible surfaces, enabling future applications such as thin architectural panels, smart lighting, and adaptive interior illumination systems.
Professor Konstantinos Daskalakis at the University of Turku in Finland stated,
“This research shows that by focusing on optical design, we can achieve the same results that once required complex chemistry. We can produce high-quality white light using fewer materials, less energy, and less waste.”
While the new single-emitter OLED demonstrates impressive efficiency and color tunability, further work is needed to optimize brightness, operational lifetime, and large-scale stability. The researchers are now focusing on refining the device’s performance under extended use and exploring how it behaves under various environmental conditions.
If these challenges are overcome, this technology could play a role in the next generation of OLED-based lighting systems—simpler, more adaptable, and more sustainable. By emphasizing structural and optical engineering over chemical complexity, the research marks an important step toward resource-efficient manufacturing in the lighting industry.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
