Carbon dots in the center of the spotlight: A full evaluation of their synthesis and understanding of their fundamental properties and applications

Due to the simplicity of fabricating the carbon dots (CQDs), which allows for scalability and cost-effectiveness, and their fascinating size-dependent physical properties, such functional materials are an enormous promise for many emergent technological applications. This has positioned these functional materials as highly promising candidates for a plethora of cutting-edge technological applications. Notable examples included solar cells, phototherapy, sensing, and environmental applications, which will be addressed in this review underscore their immense promise in emergent technologies. Here, we present a fuller understanding of the synthetic methods and physical properties of CQDs through the rationalization of many experimental and theoretical results. This includes discussions on their optical, electronic, and structural characteristics, elucidating the intricate interplay between these factors. The synthesis-structure-application triad is critically analyzed to draw connections between the fabrication methods, intrinsic properties, and functionality of CQDs. By highlighting the advancements and challenges in each of these domains, we aim to offer a comprehensive overview that can serve as a valuable resource for researchers and practitioners in the field. Finally, we hope that this review can, in principle, direct future experimental and theoretical research related to CQDs, in order to shed some light on the broad spectrum of CQDs applications a priori.