The serendipitous discovery of carbon dots has been added as a new domain of interest for materials scientists due to their extraordinary photo-physical attributes and long-term colloidal stability. This domain was more nurtured when carbon dots meet macromolecular chains. Carbon dot confined polymer matrices have diversified because of their ease of fabrication and applications in sensing, optoelectronics, semiconductors, molecular delivery, and various commercial aspects. Most promisingly, very small amounts of carbon dots have a over-the-top synergistic outcome in the presence of macromolecular systems. This review encompasses the synthesis of carbons dots, their physical properties, various fabrication strategies of polymer-carbon dots nanocomposites and applications.

This work presents the facile synthesis of heteroatom-doped fluorescent carbon quantum dots (C-dots), which could serve as an antioxidant. Herein, nitrogen, phosphorous, and sulfur codoped carbon dots (NPSC-dots) have been synthesized by a single-step hydrothermal strategy. Owing to the radical scavenging activity of the NPSC-dots, they were tested against several methods as well as in practical applications. The antioxidant ability of the NPSC-dots was efficiently utilized on plastic films by coating with these NPSC-dots. For the very first time, NPSC-dots were immobilized onto nonpolar plastic films (polypropylene) via photochemical covalent grafting to extend the shelf life of food items or storage without affecting the quality of plastic films. The NPSC-dot-coated PP film with negligible deterioration of transparency was extensively studied using scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) analysis, X-ray photoelectron spectroscopy (XPS), contact angle measurement, and thermogravimetric analysis (TGA). The fluorescent character, antioxidant ability, and durability under different solvent systems of the coated film were examined. Also, the coated films were extensively and rigorously evaluated against simulated drastic environmental conditions to ensure the durability and antifogging application.