Enhanced Optical Properties of Graphene Quantum Dots via Strategic Doping and Codoping

A recently developed class of carbon nanomaterials, known as graphene quantum dots (GQDs), has evolved, exhibiting exceptional electrical, optical, and chemical properties. In‐depth studies of GQDs have concentrated on modifying these features through doping and codoping techniques, opening up new device applications. A review on the exploration of their numerous applications in environmentally friendly and sustainable energy technologies is presented here. The doping techniques that are used to modify the electrical performance characteristics of GQDs are presented. Doping with nitrogen, sulfur, boron, and phosphorus is a commonly utilized method for modifying the bandgap of GQDs, increasing the charge carrier mobility, and enhancing their electrocatalytic activity. Codoping, a more sophisticated technique that involves introducing many dopants at once to produce synergistic effects, is investigated in detail. As dopants and codopants can encourage charge separation and boost catalytic activity for environmental remediation and hydrogen production, GQDs have also shown outstanding performance in sustainable devices. In addition, GQDs have found use in energy storage, in which they are used as supercapacitor electrode materials to increase their energy density and cycle life. Their exceptional electrocatalytic characteristics, attained through doping and codoping, have created opportunities for catalysts in fuel cells, enabling efficient energy conversion. The importance of GQDs in sensing and biosensing applications is explained. GQDs are poised to play a crucial role in the creation of novel solutions that address urgent global needs in energy, the environment, and healthcare.