650sqm Foldable LED Mesh Sceen for Stage in Shanxi,China,2023

     Chalcogenide LEDs show great potential for application in the field of display and lighting. Among them, the development of high-performance blue light devices is the key bottleneck in realizing chalcogenide full-color display and white light illumination. Compared with low-dimensional chalcogenides, although three-dimensional blue light chalcogenides have more potential for realizing high-brightness devices, the defective problems caused by the disordered crystallization process of their multi-A-site cations have seriously restricted the improvement of device performance.

Recently, the team of academician Huang Wei, Prof. Wang Jianpu and Prof. Wang Nana from Nanjing University of Technology (Flexible Electronics (Future Technology) Institute) has made a major breakthrough in the research of blue light-emitting diodes (LEDs), and the related results are summarized in the following article: “All-site alloyed perovskite for efficient and bright The results were published in Nature Communications under the title of “All-site alloyed perovskite for efficient and bright blue light-emitting diodes”. Yu Chen, a doctoral student of NUIST, is the first author of the paper, and the corresponding authors are Academician Wei Huang, Prof. Jianpu Wang and Prof. Nana Wang.

Aiming at the challenges that the competitive crystallization process of multiple A-site chalcogenide phases can lead to disordered growth and cation bias, which in turn leads to a large number of defects, the team proposed a strategy of all-site alloying of chalcogenide. Through the synergistic regulation of A/B/X multi-site, the stepwise ordered crystallization of multi-component chalcogenides was realized, and luminescent uniform chalcogenide grains were prepared.

This strategy reduces the defect density of chalcogenide films by one order of magnitude and increases the fluorescence quantum efficiency to 75%. The three-dimensional blue chalcogenide LED prepared based on this method has an external quantum efficiency of 23.3% and a brightness of 5700 cd m-2, which sets an efficiency record for a high-brightness three-dimensional blue chalcogenide LED.