常压干燥制备炭气凝胶及其电化学行为的研究

Preparation and electrochemical performance of monolithic C_m RF carbon aerogels

以甲酚为原料,添加适量的间苯二酚,在氢氧化钠催化作用下与甲醛聚合,经溶胶凝胶、溶剂置换、常压干燥和900℃炭化过程可制备纳米多孔材料炭气凝胶。N2吸附测试表明所制备炭气凝胶BET比表面积高于500m2/g,在8 nm^20 nm范围具有集中的孔径分布,适合于做双电层电容器的电极材料。采用电化学阻抗谱测试电极的电化学行为,结果显示炭气凝胶电极在1mol/L的H2SO4电解液中的体积比电容接近70 F/cm3,质量比电容最高达97 F/g。

Carbon aerogel was synthesized via a sol-gel process from the polycondensation of cresol and resorcinol with formaldehyde catalyzed by NaOH, followed by drying at ambient pressure and pyrolysis at 900℃ under inert atmosphere. Results show that this carbon aerogel has a BET surface area higher than 500 m^2/g and a fairly uniform pore size distribution in the range of 8 - 20 nm. The electrochemical behavior of such a carbon aerogel used as electrode material for an electrical double-layer capacitor was investigated by impedance spectroscopy. It is found that this carbon aerogel exhibits nearly ideal double-layer capacitance characteristics. The volume specific capacitance and the mass specific capacitance in 1 mol/L sulfur acid solution can reach as high as 70 F/cm^3 and 97 F/g.