Growth and Electrochemical Properties of Carbon Nanosheets via Microwave Plasma Enhanced Chemical Vapor Deposition

Abstract

Various morphologies and microstructures of carbon nanosheets (CNSs) were fabricated using microwave plasma enhanced chemical vapor deposition with different CH₄ ratios in Ar gas below 500 ^oC. With increasing CH₄ supplies, the CNSs decrease in flake size, as confirmed by scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The CNSs exhibit petal-like structures that consist of graphene nanosheets with a large amount of defects without impurity elements. Extending the growth time, CNSs with smaller crystalline sizes and more defects can be obtained at low CH₄ supply and easily peeled from the Cu substrate. The CNSs placed directly on the surface of a glassy carbon electrode demonstrate fast electron transfer kinetics and simultaneously detect dopamine, ascorbic acid and uric acid with high selectivity and sensitivity.

Keywords:

• Carbon nanosheets
• microwave plasma enhanced chemical vapor deposition
• synthesis
• electrochemical properties

Acknowledgments

A part of this work (Raman microscopy measurement) has been performed at the Instrument Center of the Institute for Molecular Science. We appreciate Mr. Masaki Ichihara of Hosei University for the technical support of TEM.