Synthesis and Electrical Capacitance of Carbon Nanoplates

Carbon nanoplates with diameters and thicknesses of up to approximately 1.2 μm and 18 nm, respectively, were prepared by a reaction using CaC 2 , ferrocene, and NH 4 HCO 3 as starting materials at 600 °C for 10 h. These carbon nanoplates form aggregates that have a specific surface area of up to 831 m 2 g –1 and a specific capacitance of up to 184 F g –1 at a scanning rate of 10 mV s –1 in a 3 mol L –1 H 2 SO 4 solution. Without using NH 4 HCO 3 , hexagonal carbon nanoplates with an average edge length of 500 nm and thickness of approximately 22 nm were obtained with a specific capacitance of up to 42 F g –1 . If NaN 3 or NaHCO 3 was used instead of NH 4 HCO 3 , carbon nanoplates with a curved surface or irregular circular carbon nanoplates were obtained with specific capacitances of 87 or 36 F g –1 , respectively.