Current Status and Prospects on Chemical Structure Driven Photoluminescence behaviour of Carbon Dots

Publication date: Available online 16 August 2018Source: Journal of Photochemistry and Photobiology C: Photochemistry ReviewsAuthor(s): Monoj Kumar Barman, Amitava PatraAbstractFluorescent carbon dots (C-dots) are new class of nanomaterials with widespread applications in optoelectronics, bio-imaging, catalysis, and sensing. The origin of photoluminescence of carbon dots is a debatable issue which is pretend to depend on the chemical structures such as graphitic conjugated core, molecular fluorophores inside the carbon dots and the surface defect states found to be dependent on the method of preparation. In this review, we have illustrated the important issues and challenges of the luminescent carbon dots and their potential applications. Graphitic conjugated core containing carbon dots is being synthesized usually from bulk materials like graphite, graphene and graphene oxide which exhibit size dependent photoluminescence behaviour due to quantum confinement. On the other hand, carbon dots synthesized from small molecules exhibit excitation dependent emission due to the presence of surface energy trap states which can be tuned by surface modification. Again, presence of both conjugated core and surface defect generates dual emission property. It is evident that various molecular fluorophores are produced inside carbon dots during low temperature synthesis. Hetero-atom doping is another strategy to tune the photoluminescence properties of carbon dots. Red emitting carbon dots...
Source: Journal of Photochemistry and Photobiology C: Photochemistry Reviews - Category: Chemistry Source Type: research