There is a common phenomenon in the preparation of perovskite quantum dots (QDs) by reprecipitation method that large particles were always produced with desired QDs. Understanding the fabrication mechanism can contribute to improve this phenomenon. Herein, we demonstrate a two-step strategy for synthesis of perovskite QDs and large nanoparticles (LNPs), where the growth of QDs and LNPs involves two possible pathways, the quick intercalation reaction process and the dissolution-recrystallization process. Following two pathways, we have created QDs with high photoluminescence quantum yields (ca. 46–71%), tunable size (ca. 3.2–5.4 nm) and LNPs with tunable size from 25 to 300 nm, where their emission wavelength can be tuned from 500 nm to 534 nm. Importantly, based on the comprehensive insight into the formation mechanism, we have achieved the conversion from LNPs to QDs partly through adding surfactants properly, which is expected to pave the way for the development of pure production of perovskite QDs.

通过再沉淀法制备钙钛矿量子点（QD）时，通常会出现大颗粒始终以所需QD产生的现象。了解制造机制可以有助于改善这种现象。在这里，我们演示了钙钛矿量子点和大型纳米粒子（LNP）合成的两步策略，其中量子点和LNP的生长涉及两个可能的途径，快速插层反应过程和溶解-重结晶过程。通过两个途径，我们创建了具有高光致发光量子产率（约46–71％），可调尺寸（约3.2–5.4 nm）和可调范围在25至300 nm的LNP的量子点，可在其中调节发射波长从500 nm到534 nm。重要的是，基于对形成机制的全面了解，