Doped Carbon Nanoparticles as a New Platform for Highly Photoluminescent Dots

Abstract

There have been rapid advances in the development and applications of semiconductor quantum dots (QDs) represented by CdSe/ZnS. However, a serious limitation of these QDs is the necessary use of toxic heavy metals. It is reported here that small carbon nanoparticles doped with inorganic salts serve as a highly promising new platform for brightly photoluminescent dots. The photoluminescent carbon dots with the carbon core doped with ZnO (CZnO-Dots) or ZnS (CZnS-Dots) in aqueous solutions are competitive to the commercially available CdSe/ZnS QDs in luminescence brightness.

From highly graphitic to amorphous carbon dots: A critical review

“…Common surface treatments include refl ux with HNO 3 /H 2 SO 4 to generate polar groups, 50 reduction via sodium borohydrate, 51 functionalization with PEG-based amines 19 or small molecules, 52 and coating with ZnO and ZnS. 53 Apart from those post-synthesis surface treatments, controlled carbonization approaches allow the formation of surface functionalities in situ with the synthesis of C-dots. To that end, the presence of an external corona shown in the inset in Fig.…”

Laser assisted synthesis of carbon nanoparticles with controlled viscosities for printing applications

“…Specifically, carbon nanoparticles (CNPs) have emerged as a new class of carbon-based nanomaterial with several desirable photophysical properties, chemical inertness, stability, high (aqueous) dispersity [1]. The superior biological properties of CNPs, such as low toxicity and biocompatibility, has significantly contributed in replacing traditional semiconductor quantum dots by CNPs in bioimaging, biosensor and biomolecule/drug delivery applications [2,3]. Exceptional optical and electronic properties of CNPs, include their ability for photoinduced electron transfer, photoluminescence and exceptional conductivity due to their dual role as electron donors and acceptors.…”

Progress of Luminescent Carbon Dots in Biomedicine Engineering

“…A similar effect is seen for Silicon crystals, for which a widely accepted mechanism for luminescence emission is the radioactive recombination of exactions [45]. When coated with ZnO or ZnS, the C-dots produced by Sun, et al still required further passivation by PEG 1500N for PL to occur [24]. All similar work proved that the surface state (or edge state) was the key PL mechanism in these types of Graphene C-dots.…”

“…Sun and co-workers were one of the earliest groups reported researches on C-dots [23,24]. In 2006, they have first purpose fully produced C-dots by laser ablation.…”

“…Toxicity studies have been conducted by various research groups. While the reports are few at the moment, C-dots appear to have low toxicity [2,5,[20][21][22][23][24][25]. Ray, et al performed cell viability tests on HepG2 cells, a human hepatocellular liver carcinomaline, using MTT and Trypan blue assays [47].…”