In recent years, amplified spontaneous emission (ASE) properties of all-inorganic perovskite quantum dots have attracted the interest of many researchers. Here, CsPbI₂Br quantum dots (QDs) were synthesized by the hot injection method, and the effect of the purification process on the ASE properties of QDs has been investigated. In the purification process, n-hexane and ethyl acetate (EtOAc) are used as solvent and antisolvent, respectively. The results show that the volume ratio of n-hexane vs EtOAc has a remarkable effect on the optical performance. When the volume ratio is 1:5, the QDs have a larger size which increases the light scattering and absorption cross-section, thus achieving the lowest ASE threshold of 0.301 mJ/cm². This work not only provides a facile strategy to obtain a low threshold of CsPbI₂Br QDs but also enriches the application prospects of perovskite lasers.

近年来，全无机钙钛矿量子点的放大自发辐射（ASE）特性引起了许多研究人员的兴趣。在这里，通过热注入法合成了CsPbI _{2 Br 量子点 (QD)，并研究了纯化过程对 QD 的 ASE 特性的影响。}在纯化过程中，正己烷和乙酸乙酯（EtOAc）分别用作溶剂和反溶剂。结果表明，正己烷与EtOAc的体积比对光学性能有显着影响。当体积比为1:5时，量子点具有更大的尺寸，增加了光散射和吸收截面，从而实现0.301 mJ/cm ^{2的最低ASE阈值}. 这项工作不仅为获得低阈值的 CsPbI ₂ Br QD 提供了一种简便的策略，而且丰富了钙钛矿激光器的应用前景。