Chinese researchers have achieved a world record in perovskite light-emitting diodes by constructing an all-perovskite tandem LED device and innovatively proposing the use of interlayer photon recycling to enhance the light extraction efficiency of perovskite LEDs.

The study, led by academician Huang Wei and Professors Wang Jianpu and Wang Nana from the State Key Laboratory of Flexible Electronics, was published on Tuesday in the international journal Nature under the title "High performance tandem perovskite LEDs through interlayer photon recycling."

The advancement enabled the external quantum efficiency of tandem perovskite LEDs to exceed 45 percent, setting a new world record in the field and helping open a new pathway for developing high-performance perovskite LEDs.

LED technology, which can directly convert electrical energy into light energy, has shown vast application potential in fields such as lighting and displays in recent years.

With the growing 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 focus at the forefront of global technology.

The research team achieved efficient charge injection and balance in the tandem device by optimizing the structure of the interconnecting layers.

Besides, by regulating the micro-nano structure of the perovskite emitting layers, the research team innovatively proposed a strategy to utilize the unique interlayer photon recycling effect in tandem devices.

By using the unique interlayer photon recycling effect in tandem devices, photons produced by one emitting unit can be reabsorbed and re-emitted by another perovskite layer, thereby overcoming the limitations of traditional light extraction efficiency.