am5b01419_si_001.pdf (1.53 MB)
Bandgap Engineering of Coal-Derived Graphene Quantum Dots
journal contribution
posted on 2015-04-01, 00:00 authored by Ruquan Ye, Zhiwei Peng, Andrew Metzger, Jian Lin, Jason
A. Mann, Kewei Huang, Changsheng Xiang, Xiujun Fan, Errol L. G. Samuel, Lawrence B. Alemany, Angel A. Martí, James M. TourBandgaps of photoluminescent graphene
quantum dots (GQDs) synthesized from anthracite have been engineered
by controlling the size of GQDs in two ways: either chemical oxidative
treatment and separation by cross-flow ultrafiltration, or by a facile
one-step chemical synthesis using successively higher temperatures
to render smaller GQDs. Using these methods, GQDs were synthesized
with tailored sizes and bandgaps. The GQDs emit light from blue-green
(2.9 eV) to orange-red (2.05 eV), depending on size, functionalities
and defects. These findings provide a deeper insight into the nature
of coal-derived GQDs and demonstrate a scalable method for production
of GQDs with the desired bandgaps.