嵌段共聚物对树脂基多孔炭电化学性能的影响

以间苯二酚(R)、甲醛(F)为原料,盐酸作催化剂,通过添加嵌段共聚物F127作致孔剂,利用溶液协同自组装和炭化处理制备多孔炭材料。采用扫描电镜、透射电镜和N2吸附分析不同F127加入量制得的多孔炭材料的形貌和孔隙结构,并利用直流充放电、交流阻抗技术和循环伏安法测定以上述多孔炭材料为电极的双电层电容器(EDLC)的电化学性能。结果表明:酸催化下的酚醛树脂基体网络结构在炭化过程中较好地保留了F127形成的微相结构,不同F127加入量制得的多孔炭材料比表面积在640～700 m2/g。F127/R为1.3时制得的多孔炭材料比表面积为701.2 m2/g,孔容为0.54cm3/g,其中中孔孔容0.362 cm3/g,中孔率达67.04%;在30%KOH电解质溶液中低电流密度(1 mA/cm2)充放电时的比电容为165 F/g,电流密度增大20倍,容量保持率为95%,经过5 000次循环,容量保持率达94%以上,具有良好的大电流充放电性能和循环性能。

Influence of block copolymer on property of resin based porous carbon

With resorcinol(R) and formaldehyde(F) as raw materials,hydrochloric acid as catalyst,the porous carbon material was obtained by self-assembly method of block copolymer F127 as the porogen and followed by carbonization.The appearance and pore structure of porous carbon with different F127 ratio were researched by scanning electron microscope and nitrogen gas adsorption isotherm.And the electrochemical characteristic of the porous carbon as electrode material in EDLC were studied by charging and discharging,cyclic voltammetry(CV) and AC impedence method.The results show that the microphase structure of F127 is well preserved in the process of carbonization when the net structure of phenolic resin enhances with hydrochloric acid additive.The specific surface area of porous carbon materials with different F127 ratio are between 640-700 m2/g.When F127/R is 1.3,the total pore and mesopore volume of the porous carbon reaches 0.54 cm3/g and 0.362 cm3/g respectively.In the mean time,a good capacitance performance of the sample was obtained.The specific capacitance reaches 165 F/g at the low current density of 1 mA/cm2 in the electrolyte of 30% KOH and retains 95% even as the current density switches to 20 mA/cm2 and with a constant specific capacitance over 5 000 cycles of about 161 F/g and 152.7 F/g respectively.