Transfer of Axial Chirality to the Nanoscale Endows Carbon Nanodots with Circularly Polarized Luminescence

Angew Chem Int Ed Engl. 2022 Jun 27;61(26):e202202397. doi: 10.1002/anie.202202397. Epub 2022 May 5.

Abstract

We report the synthesis, purification and characterization of chiral carbon nanodots starting from atropoisomeric precursors. The obtained atropoisomeric carbon nanodots are soluble in organic solvents and have good thermal stability, which are desirable features for technological applications. The synthetic protocol is robust, as it supports a number of variations in terms of molecular doping agents. Remarkably, the combination of axially chiral precursors and 1,4-benzoquinone as doping agent results in green-emissive carbon dots displaying circularly polarized luminescence. Dissymmetry factors of |3.5|×10-4 are obtained in solution, without the need of any additional element of chirality. Introducing axial chirality expands the strategies available to tailor the properties of carbon nanodots, paving the way for carbon nanoparticles that combine good processability in organic solvents with engineered advanced chiroptical properties.

Keywords: Atropoisomers; Carbon Nanodots; Chirality; Circularly Polarized Luminescence; Nanotechnology.