Highly Efficient Orange Emissive Graphene Quantum Dots Prepared by Acid-Free Method for White LEDs

Abstract

Graphene quantum dots (GQDs) have wide prospective applications for optoelectronic fields owing to their unique characteristics, such as tunable bandgaps, high chemical and optical stability, as well as good biocompatibility. In this work, we offered a convenient proposal to obtain uniform blue-green emissive GQDs and modified efficient orange-emitting graphene quantum dots (D-GQDs) derived from fullerene (C60) under acid-free conditions. The as-prepared D-GQDs demonstrate remarkable conversion efficiency, for which the quantum yield is up to 52.4% with an emission peak of 617 nm. Also, GQDs and D-GQDs were blended with poly­(vinyl alcohol) (PVA) to prepare transparent photoluminescent films, which show excellent flexibility and preferable white emission property meeting the requirements of commercial white LEDs.

Green synthetic nitrogen-doped graphene quantum dot fluorescent probe for the highly sensitive and selective detection of tetracycline in food samples

“…The π–π* transition is responsible for the absorption bands at 225 nm, while the n–π* transition of C O and C N bonds is responsible for the weak absorption peak at 273 nm. 49 In addition, as is shown in Fig. 4(b) , excitation and emission spectra of N-GQDs are displayed.…”

“…1(e) shows the spectra of N1s, indicating the presence of N–H (399.7 eV), N–C 3 (400.6 eV) and C–N–C (398.6 eV) on the surface of N-GQDs; 47,48 Fig. 1(f) demonstrates the N-GQD surface O 1s spectra of CO (531.0 eV) and C–OH/C–O–C (532.5 eV) and OC–OH (533.0 eV); 49,50 N atoms have been effectively doped into N-GQDs by hydrothermal reaction and functional groups such as amino groups have been generated on the original N-GQDs during the synthesis process, according to XPS analysis.…”

Ratiometric Fluorescent Probe Based on Diazotization-Coupling Reaction for Determination of Clenbuterol

“…It may be attributed to the fact that graphene serves as the mother-nucleus structure of the pyrene precursor. , The thickness was measured by a Bruker Multimode-8 atomic force microscope (AFM), and the results are shown in Figure c. The height of the GQDs was about 1–2 nm, corresponding to the thickness of 2–4 layers of graphene . Moreover, the Raman spectrum of GQDs was also recorded on a Horiba Scientific LabRAM HR Evolution Raman spectrometer (Figure d).…”

Chiral Graphene Hybrid Materials: Structures, Properties, and Chiral Applications

“…[ 269,270 ] Accordingly, GQDs have drawn rapidly growing attention from various research communities. In addition, their excellent photostability, biocompatibility, and small dimension enable them to exhibit tremendous application prospects in particular in biomedical applications, [ 271 ] sensing, [ 272 ] batteries, [ 273 ] LEDs, [ 274–276 ] and as surfactant for polymerization. [ 270 ] Particularly, the properties of small size, large specific surface area, and abundant edge sites endow GQDs with superiority for electrochemical sensing.…”