NaOH活化制备中空碳微球及其电化学性能研究

Preparation of hollow carbon microsphere by NaOH activation and its electrochemical performance

以聚苯乙烯(PS)微球为模板,制备中空碳微球。以甲基酚醛树脂(PF)为碳源,用浓硫酸对PS微球进行磺化改性,使PF包覆在PS微球上。将PF/PS复合物微球与活化剂Na OH按一定质量比混合(wNa OH∶wC=1∶1、2∶1、4∶1、6∶1、8∶1),高温活化,得到中空多孔碳微球。对样品进行氮气吸附、红外光谱、扫描电镜、透射电镜等表征,利用循环伏安、恒流充放电等测试其电化学性能。结果表明,碱碳质量比为4∶1时,碳微球比表面积最高,达2 660 m2/g,介孔较多。此时,在0.25 A/g电流密度下,材料的比电容最大,可达248 F/g,等效内阻仅2.1Ω。

Polystyrene （PS） sphere was used as template to prepare hollow carbon microsphere （HCM）. Phenolicforinaldehyde （PF） resin was selected as carbon source to cover on the surface of PS via a2SO4 modification. ThePF/PS composite were mixed with NaOH （W, aoH ： Wc=1 ： 1, 2 ： 1, 4 ： 1, 6 ： 1 and 8 ： 1） under high temperatureactivation, in order to synthetize HCM. Materials were characterized by N2 adsorption, infrared spectroscopy,scanning electron microscope and transmission electron microscope, and electrochemical performance was tested bycyclic voltammetry and constant current charging-discharging. The results show that with a mass ratio of 4 ： 1, HCMpossesses the largest surface area of 2 660 m2/g with abundant mesopores. At 0.25 A/g of current density, HCMelectrode exhibits the high specific capacitance of 248 F/g with equivalent resistance of only 2.1 Ω.