High-performance all-inorganic CsPbBr quantum dots with a low-threshold amplified spontaneous emission.

All-inorganic halide perovskite CsPbX(X = Br/Cl/I)quantum dots have gained a considerable attention in the optoelectronic fields. However, the high cost and poor stability of the prepared CsPbX quantum dots (QDs) are inevitable challenges for their future practical applications. And the high-performance CsPbX QDs are always needed. Herein, a facile and low-cost synthesis scheme was adopted to prepare the CsPbBr QDs modified by lead bromide (PbBr) and tetraoctylammonium bromide (TOAB) ligands at room temperature in open air. The prepared CsPbBr QDs exhibited a high photoluminescence quantum yield (PLQY) of 96.6% and a low amplified spontaneous emission (ASE) threshold of 12.6 µJ/cm. Stable ASE intensity with little degradation was also realized from the CsPbBr QDs doped with PMMA. Furthermore, the enhanced ASE properties of the CsPbBr QDs-doped PMMA based on distributed feedback (DFB) substrate was achieved with a lower threshold of 3.6 µJ/cm, which is 28.6% of that of the (PbBr+ TOAB)-treated CsPbBr QDs without PMMA. This work exhibits a promising potential in the on-chip light source.