Convenient synthesis of high-quality, all-inorganic lead halide perovskite nanocrystals for high purity monochrome QLED

In recent years, perovskite quantum dots (QDs) have become a new class of semiconductor materials due to their high monodispersity and adjustable emission spectra. However, there are few studies on perovskite QDs ligands, and there are some problems such as poor stability and low photoluminescence quantum yield (PLQY). Here, we prepared CsPbBr₃ QDs with excellent optical properties and crystallinity by using caesium stearate as the precursor. Besides, we systematically studied the effects of different chain length organic amines on the yield, optical properties and stability of CsPbBr₃ QDs. The experimental results show that the long-chain organic amin oleylamine and dodecylamine (DOAm) have better encapsulation properties, and the synthesised QDs have better crystallinity and stability. CsPbBr₃ QDs with PLQY of 90%were obtained by using oleic acid (OA)/DOAm as a ligand at 140°C. Moreover, a high purity monochrome quantum dot light-emitting diode was prepared.