Prof. LI Gang, Associate Director of the Otto Poon Charitable Foundation Research Institute for Smart Energy (RISE), Sir Sze-yuen Chung Endowed Professor in Renewable Energy and Chair Professor of Energy Conversion Technology, and his team have developed 3DFAPbI3 Perovskite Light-emitting Diodes (PeLEDs) that have high brightness, impressive efficiency and a long device lifetime.
The team engineered a novel technology using an alkyl-chain-length-dependent ammonium salt molecule modulation strategy. The technology employs alkylammonium salts to manage crystal orientation, control grain size, and suppress non-radiative recombination, thereby enhancing device performance. The efficient, ultra-bright and stable PeLEDs developed by the team achieved a high electroluminescence external quantum efficiency of 23.2%, a record radiance of 1,593 W sr−1 m−2, and a much-improved record lifetime of 227 h (at a high current density of 100 mA cm−2), demonstrating the best performance for “direct current (DC)-drive near-infrared PeLEDs” at high-brightness and stability levels. The research was recently published in the international energy journal Joule (https://www.sciencedirect.com/science/article/pii/S2542435124001144).
PeLEDs exhibit substantial advantages, including pure colour, a wider display colour gamut, cost effectiveness, and solution processability that provides greater flexibility in production. The team’s discovery contributes significantly to the advancement and technological breakthrough of PeLEDs.
