Influence of ligand and impurities on optical properties of carbon dots: Narrow linewidth and controllable UV-Vis spectrum

Optical properties of carbon molecules have been investigated with DFT. First, the results show that the wavelength of UV-Vis spectrum can be controlled by the number and the position of hydroxyl groups, while FWHM are only influenced by the position of hydroxyl groups. Second, study of molecules with different ligands (?Br, ?OH, ?COOH, ?NH2) have confirmed that larger ligands would make the peaks wavelength of UV-Vis spectrum shift to red and make FWHM broaden. Finally, the doping of sulfur impurity would make the peaks wavelength of UV-Vis spectrum shift to longer wavelength than those doped with boron and nitrogen impurities.

Automated summary

The optical properties of carbon molecules are influenced by the number and position of hydroxyl groups as well as the type of ligands. The doping of sulfur impurity leads to a longer wavelength shift in the UV-Vis spectrum compared to boron and nitrogen impurities.