Science News: 2021 JACS, 100-fold lifetime enhanced QD-LED

　　Journal of the American Chemical Society (IF 15.419) recently published a study based on perovskite quantum dots (QDs), which verified bright and stable high-performance light-emitting diodes.

　　Light-emitting diodes (LEDs) made of metal halide perovskite quantum dots (QD) materials have achieved high external quantum efficiency. However, when the efficiency is reduced and the quantum dot lacks surface protection, the service life of the device will be reduced. In view of the chemical instability of the material, high-efficiency perovskite quantum dots (QD) are still full of challenges.

　　In this study, the author used strained quantum dots as the center to drive perovskite crystallization. The results of the study showed that perovskite quantum dots remained stable in a thin layer of perovskite precursor solution. The new material primary red LED shows an external quantum efficiency (External Quantum Efficiency, EQE) of 18%, and maintains high performance at a brightness exceeding 4700 cd m^-2. The new material enables the LED to have a half-life of 2400 hours at an initial brightness of 100 cd m^-2, which is 100-fold stronger than the LED of the best control group. In addition to the external quantum efficiency (EQE) spectrum analysis, the quantum efficiency measurement system also provides a comparison of the short-circuit current density (Jsc) of the solar cell under the solar simulator to prove the authenticity of the experiment.