Epoxy to Carbonyl Group Conversion in Graphene Oxide Thin Films: Effect on Structural and Luminescent Characteristics

Title
Epoxy to Carbonyl Group Conversion in Graphene Oxide Thin Films: Effect on Structural and Luminescent Characteristics
Authors
J. R. RaniJuhwan Lim오주영Jung-Woo KimHyeon Suk Shin김재헌이석Seong Chan Jun
Keywords
Graphene Oxide; Luminescent characteristics; Carbonic group conversion
Issue Date
2012-09
Publisher
The Journal of Physical Chemistry C
Citation
VOL 116, NO 35, 19010-19017
Abstract
The conversion of epoxy to carbonyl group in graphene oxide (GO) thin films has been carried out via oxygen plasma treatment, and the effects of this conversion on structural and optical properties were investigated. Hydrophilicity of the prepared GO solution allows it to be uniformly deposited onto substrates in the form of thin films. High-resolution transmission electron microscopy and electron diffraction analysis confirmed 4–5 layers of the graphene oxide layers which are polycrystalline in structure, and the oxygen plasma treatment results in short-range order crystallization in graphene oxide films with an increase in interplanar spacing which can be attributed to the presence of oxygen functional groups on the graphene oxide layers. Electron energy loss spectroscopy (EELS) and Raman spectroscopy confirm the presence of the sp2 and sp3 hybridization due to the disordered crystal structures of the carbon atoms results from oxidation, and XPS analysis shows that epoxy pairs convert to more stable C═O and O–C═O groups with oxygen plasma treatment. The broad energy level distribution resulting from the broad size distribution of the sp2 clusters produces excitation-dependent photoluminescent (PL) emission in a broad wavelength range from 400 to 650 nm. Our results suggest that as oxygen pressure increases, there is a change from epoxide to carbonyl linkages which also resulted in variation in PL emission.
URI
http://pubs.kist.re.kr/handle/201004/43042
ISSN
19327447
Appears in Collections:
KIST Publication > Article
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE