A team of scientists in Japan has made a big step forward in display technology by creating a white organic light-emitting diode (OLED) that works using less than 1.5 volts.
That’s low enough to run on a single standard dry battery — a major improvement over today’s white OLEDs, which usually need over 2.5 volts to function.
OLEDs are widely used in screens for phones, TVs, laptops, and even virtual reality headsets. They produce bright, colorful images and allow for sleek, thin designs.
But white OLEDs, which are needed for lighting and backlights, have had one big problem: they use too much power.
This is mostly because creating blue light (a key part of white light) requires a lot of energy. As a result, white OLEDs haven’t been ideal for portable devices like smartwatches or battery-powered gadgets.
Now, a research team led by Associate Professor Seiichiro Izawa from the Institute of Science Tokyo has changed that.
Their work, published on July 24, 2025, in the Journal of Materials Chemistry C, shows how they developed a white OLED that runs efficiently at a much lower voltage.
The key to their success is a special technique called triplet–triplet annihilation (TTA). Here’s how it works: when electricity moves through the OLED, it creates energy in the form of “triplet states.”
These can collide and combine to create a “singlet state,” which releases blue light. This method uses much less voltage compared to traditional approaches.
But blue light alone doesn’t make white. So the team added two materials called dopants to the OLED’s light-emitting layer—one that gives off sky-blue light and another that gives off yellow light.
When blended in the right amounts, blue and yellow light combine to appear white to the human eye. The team used a perylene-based material (Tbpe) for sky-blue and rubrene for yellow.
By carefully adjusting the ratio of these dopants, the researchers were able to fine-tune the final color to produce clean white light, all while keeping the operating voltage below 1.5 volts. This is the lowest voltage ever reported for a white OLED.
This advancement could lead to new kinds of energy-saving displays and lighting devices, especially in portable electronics and wearables.
It also supports the push toward a more sustainable future, where high-quality screens don’t have to drain so much power. Although challenges like improving efficiency and long-term color stability remain, this research marks an exciting move toward smarter, greener technology.
Source: KSR.
