Summary: | 碩士 === 國立中山大學 === 化學系研究所 === 103 === Graphene, a two-dimensional carbon material, has a honeycomb-like planar structure comprised of sp2-boned carbons. Due to the extraordinary properties, graphene has been widely studied and applied in many different fields, such as, photoelectronic devices, touch panels, energy storage materials and solar cells. The chemical vapor deposition has been demonstrated to prepare large area single-layer graphene in the recent studies. The single layer graphene are produced with copper foils as catalysts and the methane as carbon sources. The high temperature (1000℃) is necessary to decompose methane to perform deposition on the surface of copper foil to yield graphene. However, the fine particle contamination on graphene surfaces are observed both in the literature and commercial products. This contamination issue of CVD graphene is problematic for relevant applications of graphene.
The quality of graphene is affected by metal substrates, so the pretreatment of metal substrates, including high temperature annealing, and electropolish was studied to reveal the correlation between graphene quality and metal substrates. In this research, we studied three pretreatment factors of hydrogen-assisted copper reduction, copper roughness under high temperature annealing, and impurity removals of copper foils via electropolish. The impurities of copper were eliminated to generate high quality graphene successfully. The sheet resistance of our high quality graphene are decreased by 3.5 times than that of the blank ones, and the improved transmittance from 96% to 98%.
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