Unveiling the structural and stability dynamics of carbon dots: Insights into size and purification

Abstract A fascinating family of nanomaterial, carbon dots (CDs), are eminent for their outstanding optical properties, chemical durability, sustainability, morphology, and size‐dependent behaviour. Upgrading their performance in different applications, including as energy storage (batteries, supercapacitor), imaging, sensors, nano medicines, fluorescence ink, and photo catalysis, requires an understanding of the relation between their size, stability, and morphology. The structural traits and size‐adaptable characteristics of CDs are formed using different synthesis routes, including carbonization, hydrothermal procedures, ultra sonication, solvothermal procedures, and microwave‐assisted procedures. A meticulous analysis is conducted of the effects of modification, via heteroatom doping, and surface functional groups on the stability and luminescence of CDs. The review emphasizes purification methods that are obligatory for removing unreacted byproducts and attaining a homogenous particle size distribution, including filtration, dialysis, size exclusion chromatography (SEC), chromatography, and centrifugation. The obstructions to preserving colloidal stability, avoiding accumulation, and improving quantum yield are also discussed. This review paper offers more insights into the optimization of CDs by establishing a relation between the stability and purification techniques and the morphological and size factors. In order to prepare homogenous, scalable, and application‐specific CDs with improved structural properties and long‐term stability, the discussion intends to direct to future research.