Surface Hydrogen‐Bond Network Construction in Perovskite Quantum Dots for Bright and Stable Near‐Infrared Light‐Emitting Diodes

ABSTRACT

Near‐infrared (NIR) light‐emitting diodes (LEDs) based on perovskite quantum dots (QDs) hold broad application prospects in night vision, biomedical treatment, and optical communications. NIR perovskite QD‐based LEDs (QLEDs) have made significant progress, with external quantum efficiencies (EQEs) exceeding 20% over the past two years, but they still suffer from low radiance and poor operational stability. Here, we used ammonium sulfamate to construct the surface hydrogen‐bond network, thereby enabling QLEDs with high radiance and long lifetime. The ammonium sulfamate forms N─H···I and N─H···O bonds with FAPbI ₃ QDs to inhibit the desorption of FA ⁺ and I ⁻ , thus stabilizing the QD surface structure. The as‐fabricated QLED showed a high radiance of 109 167 mW, a maximum EQE of 20.4% at 785 nm sr ⁻¹ m ⁻² , and an excellent operational stability of 1286 min at an initial radiance of 1000 mW sr ⁻¹ m ⁻² , representing a significant improvement over the previous reported record radiance (<40 000 mW sr ⁻¹ m ⁻² ) and record lifetime (160 min). This work offers a practical solution to enhance the radiance and operational stability of perovskite NIR QLEDs and also promotes their industrialization.