Professor Liao Liangsheng and Associate Professor Wang Yakun from the Institute of Functional Nano & Soft Materials at Soochow University have introduced a novel method for the controlled preparation of long-range ordered quantum dot thin films. They have successfully achieved a combination of high brightness, high efficiency, and high stability in perovskite quantum dot systems for the first time, offering a new strategy for the practical application of high-performance quantum dot light-emitting devices. The research findings were published in Nature on May 8th.
Schematic diagram of long-range ordered quantum dot thin films. Image provided by the research group.
The new display industry is one of the country's strategic emerging industries and a high ground for international competition. Developing new display technologies based on perovskite quantum dots is crucial for China to maintain a leading position in this industry. However, perovskite quantum dot light-emitting devices still face significant challenges in achieving high efficiency and stability at high brightness.
Addressing the key scientific issues mentioned above, researchers Liao Liangsheng and Wang Yakun, starting from mechanistic studies, deeply analyzed the key factors affecting the achievement of high brightness, high efficiency, and high stability in perovskite quantum dot light-emitting devices. They found that non-ordered perovskite quantum dot thin films are the main limiting factor. To tackle this, they proposed a dual ligand cooperative strategy, successfully preparing long-range ordered, dense, uniform, and defect-free films by combining defect passivation with the in-situ removal of small-sized quantum dots. Based on this strategy, the perovskite quantum dot light-emitting devices prepared can maintain over 20% external quantum efficiency under working conditions of 1000 nits brightness, with the working lifetime increased by over 100 times relative to similar devices, reaching the highest value in its class.
Reportedly, the Functional Nano & Soft Materials Research Institute of Soochow University is the sole corresponding unit of this paper, with Wang Yakun as the first author, Haoyue Wan, a doctoral student at the University of Toronto, as a co-first author, and Liao Liangsheng as the corresponding author of the paper. Professor Wang Suidong's research group at the Functional Nano & Soft Materials Research Institute of Soochow University provided assistance in thin film mobility characterization.
For more information on the paper, visit: https://doi.org/10.1038/s41586-024-07363-7
