In this paper diamond foam (DF) is introduced as a new material for thin-film supercapacitor application. Geometrical, structural, and electrical and electrochemical properties with respect to capacitance, electrochemical window and power are discussed in details. Diamond foam shows a 2.5 V potential window in aqueous solution. Discharge rate as high as 1000 V s −1 was measured which is three magnitudes higher than conventional supercapacitors. The power performance of diamond foam (807 W cm −3 ) approaches that of electrolytic capacitors, but the energy storage is more than one magnitude higher. Therefore, this new material is very promising for high-power micro-supercapacitor applications.
