P‐9.3: High‐Performance Red Perovskite QLEDs Based on Low‐Toxicity Zn‐Pb Alloy Perovskite QDs Passivated by Inorganic Ligands

The development of low‐cost, solution‐processable, low‐toxicity and air‐stable perovskite quantum dots (PeQDs) light‐emitting diodes (QLEDs) holds promise for next‐generation display technologies. However, especially air‐stable α‐CsPbI 3 PeQDs and corresponding light‐emitting devices still face great challenges due to their inherent ionic structural properties and phase instability. Here, a dual strategy based on Zn 2+ doping and inorganic ligand SCN‐surface passivation was developed to obtain improved, stable and near‐100% photoluminescence quantum yields (PL QYs) of a‐CsPbI 3 QDs. High‐efficiency red perovskite QLEDs are also fabricated, and the best device has a maximum brightness of 4800 cd/m 2 and an external quantum efficiency (EQE) of 5.98%. More importantly, compared with pure CsPbI 3 QLEDs, the operating stability of perovskite QLEDs based on Zn 2+ doping and SCN‐surface passivation is greatly improved in air environment, and their operating lifetimes are increased by 9 times more.