Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan.
ACS Nano. 2010 Sep 28;4(9):5285-92. doi: 10.1021/nn101691m.
Solution-based processes involving the chemical oxidation of graphite and reduction of the obtained graphene oxide (GO) sheets have attracted much attention for preparing graphene films for printed electronics and biosensors. However, the low electrical conductivity of reduced GO is still hindering the development of electronic applications. This article presents that GO sheets reduced by high-temperature alcohol vapors exhibit highly graphitic structures and excellent electrical conductivity. The sheet resistance of thin transparent films is lowered to ∼15 kΩ/◻ (>96% transparency). Field-effect transistors produced from these reduced GO sheets exhibit high effective field-effect hole mobility up to 210 cm(2)/V x s. Raman spectroscopic studies reveal that the conductivity enhancement in the low mobility regime is attributed to the removal of chemical functional groups and the formation of six-fold rings. In the high mobility regime, the growth of the graphitic domain size becomes dominant for enhancing its electrical conductivity. The excellent electrical conductivity of the reduced GO sheets promises potential electronic applications.
基于溶液的工艺过程涉及石墨的化学氧化和所得到的氧化石墨烯（GO）片的还原，这些过程已经引起了人们对于制备用于印刷电子和生物传感器的石墨烯薄膜的极大关注。然而，还原氧化石墨烯的低电导率仍然阻碍了电子应用的发展。本文提出，通过高温醇蒸气还原的 GO 片具有高度石墨化的结构和优异的电导率。薄膜的面电阻降低到 ∼15 kΩ/◻（>96%的透明度）。从这些还原的 GO 片中制备的场效应晶体管表现出高达 210 cm2/V·s 的高有效场效应空穴迁移率。拉曼光谱研究表明，低迁移率下的电导率增强归因于化学官能团的去除和六元环的形成。在高迁移率下，增大石墨化域尺寸的生长对于提高其电导率变得很重要。还原的 GO 片具有优异的电导率，有望应用于电子领域。
