Carbon Quantum Dots as Phosphors in LEDs: Perspectives and Limitations—A Critical Review of the Literature

The enduring interest in carbon quantum dots (CQDs) as photoluminescent material arises from their significant advantages over inorganic quantum dots (QDs), such as low toxicity and biocompatibility, which enables their application in bioimaging and drug delivery. This review is focused on the use of CQDs for light emitting devices (LED) technology and provides a guide on how to synthesize CQDs that emit blue, green, and red light, which is necessary to produce RGB LEDs. Consideration was given to the precursors, solvents, methods, and conditions of the processes, the excitation wavelength, the emission wavelength, and the photoluminescence quantum yield (QY). These unique, organic nanoparticles have the potential to revolutionize lighting and, above all, the electronics market due to their low cost and eco-friendliness, as well as the possibility of using various precursors, including waste.