dc.contributor.advisor |
Kwon, Soon-Yong |
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dc.contributor.author |
Chu, Jae Hwan |
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dc.date.accessioned |
2024-01-24T16:57:49Z |
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dc.date.available |
2024-01-24T16:57:49Z |
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dc.date.issued |
2016-02 |
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dc.description.abstract |
This dissertation studies that a monolithic form of Graphene Oxide (GO) sheets can be physically synthesized on a copper (Cu) surface at low temperatures (≤ 260°C), with tunable oxygen-to-carbon (O/C) composition. In our approach, we build a graphene framework on the reverse side of a Cu foil at a Cu/substrate interface by exploiting the solid-state diffusion of C atoms across a diffusion couple composed of a C-Cu/substrate. A combined experimental and theoretical study shows that the Cu foil provides an effective pathway for C diffusion, trapping the O species dissolved in Cu and enabling the formation of monolithic GO sheets on its surface after an incubation time. In contrast to chemically-derived GO, the as-synthesized GO sheets were electrically active and the O/C composition in GO can be tuned during synthesis process by controlling the O content in the Cu foil prior to the solid-state diffusion process. The resulting GO sheets exhibited tunable bandgap energy by varying the O/C composition, making them potentially useful for flexible and transparent semiconducting applications. The GO films showed the ambipolar transfer characteristics in bottom-gate field-effect transistor (FET) architectures and the electronic properties were found to correlate closely with the bandgap energy. These results suggest that monolithic, two-dimensional chemically-modified C sheets with controllable composition can be prepared at low temperatures, which is highly desirable for graphene-based device production. |
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dc.description.degree |
Doctor |
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dc.description |
Department Of Materials Science Engineering |
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dc.identifier.uri |
https://scholarworks.unist.ac.kr/handle/201301/71981 |
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dc.identifier.uri |
http://unist.dcollection.net/jsp/common/DcLoOrgPer.jsp?sItemId=000002236735 |
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dc.language |
eng |
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dc.publisher |
Ulsan National Institute of Science and Technology (UNIST) |
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dc.rights.embargoReleaseDate |
9999-12-31 |
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dc.rights.embargoReleaseTerms |
9999-12-31 |
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dc.subject |
Two-Dimensional materials, Graphene Oxide, Graphene, Tunable band gap and chemical composition |
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dc.title |
Controllable Synthesis of Multifunctional, Two-Dimensional Carbon Sheets at Low Temperatures |
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dc.type |
Thesis |
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