1 research outputs found
Uniform Graphene Quantum Dots Patterned from Self-Assembled Silica Nanodots
Graphene dots precisely controlled in size are interesting
in nanoelectronics
due to their quantum optical and electrical properties. However, most
graphene quantum dot (GQD) research so far has been performed based
on flake-type graphene reduced from graphene oxides. Consequently,
it is extremely difficult to isolate the size effect of GQDs from
the measured optical properties. Here, we report the size-controlled
fabrication of uniform GQDs using self-assembled block copolymer (BCP)
as an etch mask on graphene films grown by chemical vapor deposition
(CVD). Electron microscope images show that as-prepared GQDs are composed
of mono- or bilayer graphene with diameters of 10 and 20 nm, corresponding
to the size of BCP nanospheres. In the measured photoluminescence
(PL) spectra, the emission peak of the GQDs on the SiO<sub>2</sub> substrate is shown to be at ∼395 nm. The fabrication of GQDs
was supported by the analysis of the Raman spectra and the observation
of PL spectra after each fabrication step. Additionally, oxygen content
in the GQDs is rationally controlled by additional air plasma treatment,
which reveals the effect of oxygen content to the PL property