Division of Quantum Phases & Devices, Department of Physics, Konkuk University, Seoul 143-701, Korea.
ACS Nano. 2011 Aug 23;5(8):6417-24. doi: 10.1021/nn201601m. Epub 2011 Jul 26.
Monolayer graphene is one of the most interesting materials applicable to next-generation electronic devices due to its transport properties. However, realization of graphene devices requires suitable nanoscale lithography as well as a method to open a band gap in monolayer graphene. Nanoscale hydrogenation and oxidation are promising methods to open an energy band gap by modification of surface structures and to fabricate nanostructures such as graphene nanoribbons (GNRs). Until now it has been difficult to fabricate nanoscale devices consisting of both hydrogenated and oxidized graphene because the hydrogenation of graphene requires a complicated process composed of large-scale chemical modification, nanoscale patterning, and etching. We report on nanoscale hydrogenation and oxidation of graphene under normal atmospheric conditions and at room temperature without etching, wet process, or even any gas treatment by controlling just an external bias through atomic force microscope lithography. Both the lithographically defined nanoscale hydrogenation and oxidation have been confirmed by micro-Raman spectroscopy measurements. Patterned hydrogenated and oxidized graphene show insulating behaviors, and their friction values are several times larger than those of graphene. These differences can be used for fabricating electronic or electromechanical devices based on graphene.
单层石墨烯因其传输性质而成为适用于下一代电子设备的最有趣材料之一。然而，石墨烯器件的实现需要合适的纳米级光刻技术以及打开单层石墨烯带隙的方法。纳米级氢化和氧化是通过表面结构修饰和制造纳米结构（如石墨烯纳米带）来打开能隙的有前途的方法。到目前为止，由于石墨烯的氢化需要由大规模化学修饰、纳米级图案化和蚀刻组成的复杂过程，因此很难制造由氢化和氧化石墨烯组成的纳米级器件。我们通过原子力显微镜光刻术仅通过控制外部偏压，在正常大气条件下和室温下无需蚀刻、湿法工艺甚至任何气体处理，报告了石墨烯的纳米级氢化和氧化。通过微拉曼光谱测量证实了光刻定义的纳米级氢化和氧化。图案化的氢化和氧化石墨烯表现出绝缘行为，其摩擦值比石墨烯大几倍。这些差异可用于制造基于石墨烯的电子或机电设备。
