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

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 degrees C. 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.