The Effect of Thermal Reduction on the Photoluminescence and Electronic Structures of Graphene Oxides
Abstract
Electronic structures of graphene oxide (GO) and hydro-thermally reduced graphene oxides (rGOs) processed at low temperatures (120–1806C) were studied using X-ray absorption near-edge structure (XANES), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS). C K-edge XANES spectra of rGOs reveal that thermal reduction restores C 5 C sp2 bonds and removes some of the oxygen and hydroxyl groups of GO, which initiates the evolution of carbonaceous species. The combination of C K-edge XANES and Ka XES spectra shows that the overlapping p and p* orbitals in rGOs and GO are similar to that of highly ordered pyrolytic graphite (HOPG), which has no band-gap. C Ka RIXS spectra provide evidence that thermal reduction changes the density of states (DOSs) that is generated in the p-region and/or in the gap between the p and p* levels of the GO and rGOs. Two-dimensional C Ka RIXS mapping of the heavy reduction of rGOs further confirms that the residual oxygen and/or oxygen-containing functional groups modify the p and s features, which are dispersed by the photon excitation energy. The dispersion behavior near the K point is approximately linear and differs from the parabolic-like dispersion observed in HOPG.
- Authors:
-
- Tamkang Univ., Taipei (Taiwan). Dept. of Physics
- National Taiwan Univ., Taipei (Taiwan). Dept. of Materials Science and Engineering
- National Univ. of Kaohsiung (Taiwan). Dept. of Applied Physics
- Univ. of South Africa, Johannesburg (South Africa). College of Science, Engineering and Technology. Dept. of Physics
- Univ. of Science and Technology of China, Hefei (China). National Synchrotron Radiation Lab.
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division
- OSTI Identifier:
- 1624700
- Grant/Contract Number:
- AC02-05CH11231
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Scientific Reports
- Additional Journal Information:
- Journal Volume: 4; Journal Issue: 1; Journal ID: ISSN 2045-2322
- Publisher:
- Nature Publishing Group
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 42 ENGINEERING; 36 MATERIALS SCIENCE; Science & Technology - Other Topics; ELECTRONIC PROPERTIES AND DEVICES; ELECTRONIC PROPERTIES AND MATERIALS
Citation Formats
Chuang, C. -H., Wang, Y. -F., Shao, Y. -C., Yeh, Y. -C., Wang, D. -Y., Chen, C. -W., Chiou, J. W., Ray, Sekhar C., Pong, W. F., Zhang, L., Zhu, J. F., and Guo, J. H. The Effect of Thermal Reduction on the Photoluminescence and Electronic Structures of Graphene Oxides. United States: N. p., 2014.
Web. doi:10.1038/srep04525.
Chuang, C. -H., Wang, Y. -F., Shao, Y. -C., Yeh, Y. -C., Wang, D. -Y., Chen, C. -W., Chiou, J. W., Ray, Sekhar C., Pong, W. F., Zhang, L., Zhu, J. F., & Guo, J. H. The Effect of Thermal Reduction on the Photoluminescence and Electronic Structures of Graphene Oxides. United States. https://doi.org/10.1038/srep04525
Chuang, C. -H., Wang, Y. -F., Shao, Y. -C., Yeh, Y. -C., Wang, D. -Y., Chen, C. -W., Chiou, J. W., Ray, Sekhar C., Pong, W. F., Zhang, L., Zhu, J. F., and Guo, J. H. Thu .
"The Effect of Thermal Reduction on the Photoluminescence and Electronic Structures of Graphene Oxides". United States. https://doi.org/10.1038/srep04525. https://www.osti.gov/servlets/purl/1624700.
@article{osti_1624700,
title = {The Effect of Thermal Reduction on the Photoluminescence and Electronic Structures of Graphene Oxides},
author = {Chuang, C. -H. and Wang, Y. -F. and Shao, Y. -C. and Yeh, Y. -C. and Wang, D. -Y. and Chen, C. -W. and Chiou, J. W. and Ray, Sekhar C. and Pong, W. F. and Zhang, L. and Zhu, J. F. and Guo, J. H.},
abstractNote = {Electronic structures of graphene oxide (GO) and hydro-thermally reduced graphene oxides (rGOs) processed at low temperatures (120–1806C) were studied using X-ray absorption near-edge structure (XANES), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS). C K-edge XANES spectra of rGOs reveal that thermal reduction restores C 5 C sp2 bonds and removes some of the oxygen and hydroxyl groups of GO, which initiates the evolution of carbonaceous species. The combination of C K-edge XANES and Ka XES spectra shows that the overlapping p and p* orbitals in rGOs and GO are similar to that of highly ordered pyrolytic graphite (HOPG), which has no band-gap. C Ka RIXS spectra provide evidence that thermal reduction changes the density of states (DOSs) that is generated in the p-region and/or in the gap between the p and p* levels of the GO and rGOs. Two-dimensional C Ka RIXS mapping of the heavy reduction of rGOs further confirms that the residual oxygen and/or oxygen-containing functional groups modify the p and s features, which are dispersed by the photon excitation energy. The dispersion behavior near the K point is approximately linear and differs from the parabolic-like dispersion observed in HOPG.},
doi = {10.1038/srep04525},
journal = {Scientific Reports},
number = 1,
volume = 4,
place = {United States},
year = {Thu Apr 10 00:00:00 EDT 2014},
month = {Thu Apr 10 00:00:00 EDT 2014}
}
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