A simple, facile and green hydrothermal method was developed in the synthesis of water-soluble nitrogen-doped carbon dots (N-CDs) from streptomycin. The as-prepared N-CDs displayed bright blue fluorescence under the irradiation of UV light, together with a high quantum yield of 7.6% and good biocompatibility as demonstrated by the cell viability assay. Thus, the N-CDs can be used as fluorescent...

Graphene can be p-type or n-type doped by introduction of specific species. Doping can modulate the electronic properties of graphene, but opening a sizable-well-tuned bandgap is essential for graphene-based tunable electronic devices. N-doped graphene is widely used for device applications and is mostly achieved by introducing ammonia into the synthesis gas during the chemical vapor deposition...

Abstract A novel nitrogen-doped carbon quantum dots (N-CDs) were prepared by the microwave irradiation method. The fluorescence quenching effect of Co(II) on N-CDs was studied in sodium dodecyl sulfate (SDS) medium and sensitized SDS. linear range calibration curve for determination 0.17µg/mL-11.8µg/mL limit detection 0.052µg/mL. method has been applied samples with satisfactory results.

Prolonged exposure to ultraviolet (UV) radiation from the sun can result in several skin problems, such as accelerating aging, burns, blemishes, or even cancer. Even when wearing clothes, there is still a risk that user will be exposed UV and suffer damage. Therefore, it necessary apply anti-UV treatments clothes fabrics used, so users become safe. Nitrogen doped graphene quantum dots (N-GQD) t...

The co-doping of graphene with nitrogen and sulfur was investigated aiming at understanding their interactions with the presence of oxygen in graphene. The co-doped graphene (NS-G) was synthesized via a one-pot hydrothermal route using graphene oxide as starting material and L-cysteine, an amino acid containing both N and S, as the doping agent. The obtained NS-G with a three-dimensional hierar...

A model that explains the unusual characteristics of the AlGaAs/GaAs modulation-doped field-effect transistor (MODFET) with InAs quantum dots incorporated in the GaAs channel is presented. It is shown that the negative charge of electrons confined in quantum dots decreases the threshold gate–drain voltage at which the channel is fully depleted. This provides an impact ionization of quantum dots...

Graphene quantum dots (GQDs) have drawn tremendous attention on account of their numerous alluring properties and a wide range of application potentials. Here, we report that hydrophilic and hydrophobic N-doped GQDs can be prepared via exfoliating and disintegrating graphite flakes. Various spectroscopic characterizations including TEM, AFM, FTIR, PL, XPS, and Raman spectroscopy demonstrated th...