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

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 j 3.5 j × 10 À 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.

Amine‐Rich Carbon Dots as Novel Nano‐Aminocatalytic Platforms in Organic Synthesis

“…[3] Furthermore, an appealing trait of the "bottom-up" synthesis is that part of the properties of the reagents could be retained in the nanoparticles structure. [25] As examples, it was possible to envision the production of chiral CDs starting from ad hoc enantiopure chiral organic compounds, [26,27] or electrochemically-rich CDs starting from quinones. [28] Despite the straightforward preparation and the versatility of the synthetic protocols, the purification of CDs can be nontrivial.…”

Transmitting biomolecular chirality into carbon nanodots: a facile approach to acquire chiral light emission at the nanoscale

“…20 However, circularly polarized luminescence (CPL), the luminescence counterpart of CD, is gaining vast attention in recent years due to its potential to explore the excited state chirality. 21,22 In this regard, CPL properties of various nanomaterials such as semiconductor QDs and perovskite nanocrystals have been investigated. 23 The chiral emissive properties of CNDs have also been studied by exploiting template-assisted methods.…”

Circularly Polarized Luminescence of Achiral Carbon Dots in Bi‐Solvent Systems Triggered by Supramolecular Self‐Assembly

“…Simply put, CDs can serve as a potential luminescent counterpart to co‐assemble with various chiral template hosts such as cellulose nanocrystals, chiral glutamate and phenylalanine‐derived gelators to realize the transfer and amplification of chirality, thereby endowing CDs with controllable CPL properties [5] . And another way was reported by Prato et al., they innovatively employed atropisomers as precursors of CDs and have successfully shown that axially chiral information can be retained in the synthesis of CDs, leading to CDs displaying CPL as an intrinsic property [6] . Nowadays, developing more methods to realize CPL of CDs is of great significance for exploring new designs of CPL materials and their potential applications.…”

“…[5] And another way was reported by Prato et al, they innovatively employed atropisomers as precursors of CDs and have successfully shown that axially chiral information can be retained in the synthesis of CDs, leading to CDs displaying CPL as an intrinsic property. [6] Nowadays, developing more methods to realize CPL of CDs is of great significance for exploring new designs of CPL materials and their potential applications.…”