The emission wavelength of organic-inorganic hybrid perovskite quantum dots (QDs) can be tuned by controlling reaction time relevant to the halide exchange. It is because halide exchange with different time would lead to different molar ratio of halides in perovskite QDs such as Cl and Br. Here, to research the ligand's effect on the halide exchange, this work synthesized 3-mercaptopropionic acid (MPA)-capped CH3 NH3 PbBrx Cl3-x QDs. It was found that SH- of MPA appeared to inhibit the halide exchange during the reation. Moreover, although the MPA-capped CH3 NH3 PbBrx Cl3-x QDs did not contain the chiral centre, they exhibit the optical rotation. This may provide a method for chirality manipulation of perovskite.

中文翻译：

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调整3-巯基丙酸封端的有机-无机杂化钙钛矿的光学性质和旋光性。

可以通过控制与卤化物交换有关的反应时间来调节有机-无机杂化钙钛矿量子点（QDs）的发射波长。这是因为不同时间的卤化物交换将导致钙钛矿型量子点（如Cl和Br）中卤化物的摩尔比不同。在这里，为了研究配体对卤化物交换的影响，这项工作合成了3-巯基丙酸（MPA）封端的CH3 NH3 PbBrx Cl3-x QDs。发现MPA的SH-似乎在反应期间抑制卤化物交换。此外，尽管MPA封端的CH3 NH3 PbBrx Cl3-x QD不包含手性中心，但它们具有旋光性。这可以提供用于钙钛矿手性操纵的方法。