Jump to main content
Jump to site search


Optical and Electronic Properties of Graphene Quantum Dots with Oxygen-Containing Groups: a Density Functional Theory Study

Abstract

Effects of five types of oxygen-containing functional groups ( COOH, COC , OH, CHO, and OCH3) on graphene quantum dots (GQDs) are investigated using time-dependent density functional theory (TD-DFT). Their absorption spectra and HOMO–LUMO gaps are quantitatively analyzed to reveal the influence of different oxygen-containing groups including their locations and quantities on optical properties of GQDs. Compared with those on the edge of GQD plane, oxygen-containing groups located on the surface have more evident effects on optical properties. The calculated HOMO–LUMO gaps of pristine GQDs and edge-functionalized GQDs with -OH, -COOH, -OCH3, -CHO, and -COC- are 2.34, 2.32, 2.31, 2.30, 2.27, and 2.15 eV, respectively, whereas the HOMO–LUMO gaps of surface-functionalized GQDs with the groups above are 0.36, 0.32, 0.37, 0.39, and 1.86 eV, respectively. Interestingly, the influence of surface and edge functionalization on the HOMO–LUMO gap of GQDs is almost opposite. The absorption process is investigated along with excited state analysis, which includes the oscillator strengths, natural transition orbital, and charge difference density . It is found that functionalization on the basal plane greatly change the distribution of electron density in surface-functionalized GQDs.

Back to tab navigation
Please wait while Download options loads

Supplementary files

Publication details

The article was received on 09 Feb 2017, accepted on 15 May 2017 and first published on 15 May 2017


Article type: Paper
DOI: 10.1039/C7TC00631D
Citation: J. Mater. Chem. C, 2017, Accepted Manuscript
  •   Request permissions

    Optical and Electronic Properties of Graphene Quantum Dots with Oxygen-Containing Groups: a Density Functional Theory Study

    J. Feng, H. Dong, L. Yu and L. Dong, J. Mater. Chem. C, 2017, Accepted Manuscript , DOI: 10.1039/C7TC00631D

Search articles by author