A Customizable Perovskite Quantum Dots Platform for Visual Fluorescent Discrimination of Molecular Homologs and...

Fluorescence-based enantioselective recognition remains a significant challenge, often hampered by complex probe synthesis and limited versatility. Herein, we report a simple yet powerful fluorescent sensing platform based on chiral polymer-coated perovskite quantum dots (QDs) for the comprehensive recognition of small organic molecules. By grafting a chiral recognition site (R)-2-butyl acrylate or (S)-2-butyl acrylate onto polyacrylic acid (PAA), we synthesized chiral copolymers, PAA^R or PAA^S, and used them to fabricate CsPbBr₃@PAA^R or CsPbBr₃@PAA^S QDs, respectively. These QDs exhibit quasi-mirror symmetric fluorescence responses, enabling rapid, naked-eye discrimination of (R)- and (S)-2-butanol enantiomers. Furthermore, the parent achiral CsPbBr₃@PAA QDs system allows for full structural identification of C_1-C₄ monohydric alcohol homologs and isomers, as well as other organic homologs like sulfoxides and formamides, based on their distinct fluorescence color transitions. The recognition mechanism, probed by in situ IR and NMR spectroscopy combined with computational simulations, is attributed to hydrogen-bonding interactions that modulate the alcohol diffusion rate through the polymer layer. This work provides a customizable and robust platform for advanced chemical sensing.