双电层电容器用中孔炭微球/活性炭复合电极的制备

采用水热法合成比表面积1850m2/g、粒径lμm的中孔炭微球(MCM);而后将所制MCM加入比表面积为3200m2/g的超级活性炭(HSAC)中制成用于双电层电容器的复合电极材料,并研究了该复合电极材料的电化学性能.结果表明:在比表面积为3200m2/g的HSAC中添加质量分数20%的MCM后,其颗粒接触内阻、离子扩散内阻明显降低;在6mol/L的KOH电解液体系中,在12A/g的电流密度下,其比电容仍能稳定在230F/g.而在同样的条件下,纯HSAC和纯MCM的比电容仅分别为190F/g和148F/g.复合电极在大电流下电化学性能的提高应归因于MCM合适的粒径、中孔结构及其较高的比表面积.

Preparation of mesoporous carbon microsphere/activated carbon composite for electric double-layer capacitors

Mesoporous carbon microspheres (MCMs) with specific surface area and diameter of 1850 m2/g and 1 μm,respectively, were synthesized using the solvothermal method. When mass fraction 20% of these were added to a high surface area-activated carbon (HSAC: 3200m2/g) its interfacial resistance and ion diffusion resistance decreased significantly. The specific capacitance of the composite electrode is 230F/g in 6 mol/L KOH electrolyte, whereas those of pure HSAC and MCMs are only 190 and 148F/g, respectively, at a high current density of 12A/g. The improvement in electrochemical performance of the HSAC electrode at high current densities is attributed to the small particle diameter, mesoporous structure and high specific surface area of the added MCMs.