Ultra-narrow bandwidth red-emission carbon quantum dots and their bio-imaging

One-step solvothermal method was used to synthesize red fluorescent carbon quantum dots (R-CQDs) with ultranarrow bandwidth emission by using the titanyl-phthalocyanine (TiOPc) as the reaction precursor and ethanol as the organic solvent. We characterized the structural and optical properties of the R-CQDs by a variety of spectroscopic methods such as photoluminescence. Our studies have shown that the photoluminescence properties of R-CQDs are independent of the excitation wavelength. The strongest emission peak is at 674 nm, the full width at half maximum (FWHM) is only 23.2 nm, and the quantum yield (QY) is 7.54%. In addition, we also studied the application of the R-CQDs as a potential diagnostic marker. It was observed that the R-CQDs could enter the aloe tissue. The R- CQDs reported here have a narrow width and excellent QY characteristics, which can be attributed to the surface and edge C = O, C = N groups and Ti doping in the R-CQDs. Such R-CQDs can be widely used in the fields of display device, cell labelling and bio-imaging.

Automated summary

Red fluorescent carbon quantum dots (R-CQDs) with ultranarrow bandwidth emission were synthesized using a one-step solvothermal method. The R-CQDs were characterized using various spectroscopic methods including photoluminescence. The photoluminescence properties of R-CQDs were found to be independent of the excitation wavelength, with the strongest emission peak at 674 nm, a full width at half maximum (FWHM) of only 23.2 nm, and a quantum yield (QY) of 7.54%. Additionally, the R-CQDs showed potential as a diagnostic marker, as they were able to enter aloe tissue. The narrow emission width and excellent QY of the R-CQDs can be attributed to the surface and edge C = O, C = N groups, as well as Ti doping. Therefore, R-CQDs have wide applications in display devices, cell labeling, and bio-imaging.