Considerable effort has been devoted to the development and characterization of new electrode materials with improved performance for applications in energy storage devices such as electrochemical supercapacitors. 1-3 Supercapacitors are unique devices exhibiting 20 to 200 times greater capacitance than conventional capacitors mainly due to the high surface area of the electrodes used or to highly functionalized surfaces. [5][6][7] The large capacitance exhibited by these systems arises from double layer (dl) capacitance (i.e., from charge separation across the electrode/electrolyte interfacial dl) often in combination with pseudocapacitance. This pseudocapacitance is associated with redox-type reactions due to the presence of surface chemical groups and/or to participation of adsorbed species on its surface. 5-7 Studies currently in progress in this area include materials such as carbons, metal oxides, and conducting polymers. For industrial use, these electrode materials must be easy to produce and inexpensive, and exhibit high energy and power densities, high cycle life, and good stability.Carbon materials meet the majority of the requirements mentioned above. They are available in a variety of structures (powder, fibers, thin solid, large block, and porous sheets) and generated from different organic precursors, which make them suitable for various applications. 8-11 However, constant improvements are needed especially in terms of energy and power. In the case of supercapacitors, carbon microcellular foams (MFs) synthesized using a sol-gel technique have been investigated as electrode materials. 12 Increasing interest for this type of material is essentially due to the possibility for control of geometric parameters (pore diameter, surface area) during synthesis. Carbon aerogels are commonly made by polymerization of resorcinol-formaldehyde (RF) 13 and from polyacrylonitrile (PAN) solution. 14,15 In spite of their interesting characteristics, a supercritical drying step is required during the synthesis (to prevent the collapse of the porous structure) which makes them economically unsuitable for industrial applications. To circumvent this problem, other techniques have been developed in our laboratory, such as inverse emulsion 16 and the use of thin films dried in air. [17][18][19] Using these last two techniques, it is possible to avoid supercritical drying. These raw and inexpensively produced materials can be modified in order to improve their performances, e.g., by increasing their surface areas. Indeed, as presented above, large surface areas are required to obtain highly capacitive materials. Therefore, activation processes have been developed on a wide range of carbon materials in order to increase the overall surface area by the creation and widening of existing pores electrochemically, thermally or by the action of chemical oxidative agents. 13,20,[21][22][23][24][25][26] Chemical modification of the surface also occurs during such activation.The present work describes our first results concerning th...
