What They Say
The Ural Federal University, based in Yekaterinburg, Russia, working with scientists in China have published a paper in Advanced Functional Materials that explains how a group developed nanostructures (hemispheres) several nanometers high to improve the light extraction of perovskite LEDs. The group achieved an EQE of 21.2% and extended the lifetime by a factor of 1.75X.
“At a wavelength of 666 nanometers and an initial luminosity of 100 candel/square meter, the resulting peak quantum efficiency of the modified LED was observed for nearly 4807 hours. This is the longest high performance lifetime compared to similar PeLEDs available in the world. For example, the lifetime of the LED with the same brightness parameters and efficiency of 21.3% is only 5 minutes. The efficiency of the LED, whose lifetime at a similar brightness is 694 hours – 6.2%,”
said Ivan Zhidkov.
As well as improving EQE, the technique meant a lower operating temperature, which helped with the lifetime extension.
What We Think
Russia has a tradition of basic research in physics and devices. Around 15 years ago, on a flight from Moscow to Seoul, I sat next to a lady who was visiting her husband in Korea. He was a Professor of Physics from Russia who was working for a limited period at Seoul Semiconductor. She said that he would earn enough in a year or two to secure his income in retirement in Russia. (BR)
