Synthesis and field emission properties of carbon nanosheets

A nanometer edged two-dimensional graphite structure, carbon nanosheet, was synthesized by inductively coupled radio-frequency plasma enhanced chemical vapour deposition on a variety of substrates, including metals, semiconductors and insulators. The carbon nanosheets were characterized by scanning electron microscopy, high resolution transmission electron microscopy and Raman spectroscopy. Edges of nanosheets had a uniform thickness of about 1 nm. Typical nanosheets consisted of only a few atomic layers and had a graphitic structure. The high density of atomic scale vertical graphitic edges are potential sites for electron field emission. The carbon nanosheets had a turn-on (threshold 10/spl mu/A/cm/sup 2/) field of about 5 V//spl mu/m and a metallic behavior based on a linear Fowler-Nordheim plot. This sheet-like carbon nanostructure is expected to be a robust edge emitter.