Researchers develop high-efficiency pure red light-emitting diodes through surface modification of perovskite QDs

Researchers from Korea's Daegu Gyeongbuk Institute of Science and Technology (DGIST), Ulsan National Institute of Science and Technology (UNIST) and Institute for Basic Science (IBS) recently developed high-performance, skin-attachable perovskite pure red light-emitting devices to create various forms of wearable displays.

The team developed these devices through selective surface modification of perovskite quantum dots, expecting their future use in diverse wearable products. As traditional red perovskite materials were unsuitable for high-performance wearable displays due to their low stability and electrical properties, the research team created pure red light-emitting devices through the simple surface modification of the perovskite light-emitting layers, thus significantly improving their stability and electrical properties.

 

In previous perovskite fabrication processes, surface modification was performed using iodine, a halogen element. However, the research team replaced iodine with bromine (Br), a halogen element with higher electronegativity, and increased the size of the perovskites beyond the original dimensions. This resulted in an improved surface-to-volume ratio with the same "band gap energy," leading to the development of pure red light-emitting devices with exceptional stability and electrical properties.

Professor Jiwoong Yang from DGIST stated, "By selectively modifying the surface of perovskite quantum dots, we improved their stability and electrical properties, ultimately achieving an external quantum efficiency (EQE) of up to 19.8%. This research brings us closer to the commercialization of pure red perovskite displays."

Professor Moon Kee Choi from UNIST added, "The newly developed light-emitting devices are expected to be widely applied not only in perovskite LED-based displays but also in VR, AR, and smart wearable device development."

Posted: May 12,2024 by Roni Peleg