| Supercapacitors have been arousing more attentions in newly developed fields like electronics, new power sources etc. Since their performance mainly depends on the anode materials, it has been extensively pursued to get high quality materials with low cost and easy ways.Carbon foams with three dimensional networks and microsize walls were prepared from a pitch and a phenolic resin respectively through foaming, carbonization. The carbon foams were activated with steam activation. A microporous template carbon was synthesized from furfuryl alcohol with NaY zeolite as the template. Graphene was converted from natural crystalline flake graphite by modified hummers'method. The manufactured carbons, which could be classified into microporous and opened planar structured carbons, were evaluated with cyclic voltammetry and constant current coulometry for electrode materials of supercapacitors. The effect of pore size and electrolyte ions on capacitance was discussed.A thermalplastic phenolic resin blinded with hexamine was heated to foam at about 210℃, and then heated to 700℃to transform into carbon foams, among which the sample derived with 12wt% hexamine heated at 10℃/min. The carbon foam was activated at 700-850℃for 60-180min with water steam metered by water flow of 1.0-2.0mL/min, into activated carbon foams with specific surface area of 474-1287m2/g and pore diameter of 0.64-5.0nm. While a pitch with soft-point of 285℃was blown to pitch foams by supercritical solvent and successively oxidized and carbonized to get carbon foams, on which the solvent addition, foaming temperature, and initial pressure were the key influencial factors. The sample foamed under the conditions of 30wt% toluene, initial pressure of 3.0MPa, and foaming temperature of 300℃. was activated at 850℃for 60-180min with water steam metered by water flow of 1.0mL/min, into activated carbon foams with specific surface area of 399-953m2/g and pore diameter of 0.59-5.0nm.The electrochemical performances of the two activated carbon foams was studied, the phenolic resin based and the pitch based with specific surface area of 961m2/g and 953m2/g respectively. When measured at the current of 1.0mA, the two samples owned the similar capacitances of 117F/g and 112.5F/g, while measured at 50mA, their capacitances differed a lot, with 60.5F/g for the former and 28.3F/g for the later. Compared with activated carbon fiber with specific surface area of 1297m2/g, the activated resin carbon foam with specific surface area of 1267 m2/g showed a comparable specific capacitance of 142.4 F/g against 169.8F/g at 1.0mA and decreased to 77.1F/g against 121F/g at 50mA, indicating that activated carbon foam would be a good electrode material with easy process even a little lower performance compared with activated carbon fiber.Template carbons were prepared from furfuryl alcohol by using NaY zeolite as the template through soaking, polymerizing, carbonizing at 700-800℃, template removing with HF, with pores sized at 1.0nm and 1.6nm and specific surface area of 578-826m2/g. The sample with specific surface area of 826m2/g were measured in four different electrolytes of NaOH, KOH, NaCl and Na2SO4, showing that the performance in NaOH was the best with capacitance of 150.4F/g at 1.0mA, while that in Na2SO4 was the worst, with capacitance of 58.7F/g. The reason could be interpreted as smaller ions diffused more easily in the micropores.Graphene was converted from a crystal flake graphite through oxidizing by modified Hummers'method, dispersing by supersonic and reducing by NaBH4, with specific surface area of 358m2/g. The specific capacitance could reach 138.6F/g at 10mA with a capacitance efficiency of 98%, much higher than the micropore carbons based its specific surface area, which could be mainly benefited from its opened planar structure. The cyclic voltammetry showed the graphene had good double layer capacity.
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