Fluorescent N-Doped Graphene Quantum Dots Embedded in Transparent Polymer Films for Photon-Downconversion Applications

In this work, we demonstrate a simple, facile, and efficient one-pot synthesis of polymer–quantum dot nanocomposite films where nitrogen-doped graphene quantum dots (N-GQDs) were homogeneously dispersed in UV-curable, transparent polymer host matrix via the thiol–ene “click” reaction pathway. The highly fluorescent NOA–NGQD nanocomposite films exhibited strong hydrophobicity with water contact angle (>69°) owing to restructuring of the polymer chain networks. The various functional groups of the N-GQD surface, as carbonyl, amine, and hydroxyl groups, provided more interactive sites and low agglomeration to develop the strong electrostatic interactions between the NOA and N-GQDs, resulting in flexible NOA–NGQDs nanocomposites. Thus, obtained NOA–NGQD nanocomposites exhibited high transparency (>90%), low band-gap, and strong fluorescence spectral peak (>500 nm) after the homogeneous inclusion of N-GQDs in the NOA polymer matrix. This study paves the way to diverse applications of functionalized GQDs as well as transparent polymers for the development of hydrophobic polymer–QD nanocomposites by using UV catalyzed thiol–ene chemistry. Hence, as synthesized nanocomposite films would be widely applicable in flexible electronic display devices, light emitting diodes (LEDs), and optoelectronic applications.