Recently, the teams of Academician Huang Wei, Professor Wang Jianpu, and Professor Wang Nana from the National Key Laboratory of Flexible Electronics have made significant progress in the field of perovskite light-emitting diodes (LEDs). The research team has successfully constructed a fully perovskite stacked LED device and innovatively proposed the use of interlayer photon cycling effect to improve the light extraction efficiency of perovskite LEDs, breaking the external quantum efficiency of stacked perovskite LEDs by over 45% and once again setting a world record in this field. Undoubtedly, this breakthrough has opened up a new path for the development of high-performance perovskite LEDs. On November 11th, the related research results were published in the top international academic journal Nature under the title "High Performance Tandem Perovskite LEDs through Interlayer Photon Recycling". Nanjing University of Technology is the first author and corresponding author unit of the paper.

Light emitting diode technology can directly convert electrical energy into light energy, and has shown broad application prospects in fields such as lighting and display in recent years. With the continuous increase in market demand for high-quality displays and lighting, the development of new LED technologies that combine high brightness, low cost, and flexibility has become a research hotspot at the forefront of world technology. Perovskite LED has attracted much attention due to its advantages of solution processability, high color purity, and low preparation cost. Its performance has gradually approached the level of commercial organic LED. At present, commercial organic LED display screens generally adopt a stacked device structure, which achieves brightness superposition by connecting multiple light-emitting units in series at the same current density, and has become a key path to improve LED brightness and service life. However, the current external quantum efficiency of stacked perovskite LEDs is still less than 10%, and even much lower than that of single junction devices, seriously restricting their commercialization process.