氢氧化钾活化法制备淀粉活性炭电极材料

以KOH为活化剂、氧化交联淀粉为原料制备了超级电容器用电极材料.最佳工艺条件是:活化温度850℃,活化保温1.5 h,碱炭质量比为2∶1.在该条件下制备的淀粉活性炭具有较高的比表面积(1 493.9 m2/g)和高比容量(218 F/g).通过氮吸附表征其孔结构.以其作为电极材料组装在模拟超级电容器中进行充放电性能和循环伏安法测试,在300 mg/g KOH水系电解质溶液、较高电流密度下,最佳制备工艺条件下所制备的活性炭表现出较好的电容特性.

Preparation of the Starch Actived Carbon for the Electrode Materials with KOH Activation

The activated carbon for the electrodes in supercapacitors was fabricated from oxidized-crosslinking starch by chemical activation with potassium hydroxide.The activated carbons with best performance could be synthesized at the following condition:activation temperature 850 ℃,m(KOH)∶m(C) is 2/1,and the activation time 1.5 h.In this condition,synthetical activated carbons presented higher BET surface area(1 493.9 m2/g) and high specific capacitance(218 F/g).The pore structure of the starch activated carbon was assessed based on N2 at 77 K adsorption.The electrochemical performance of capacitors was determined using galvanostatic charge/discharge characteristics and cyclic voltammetry.It shows that even in the high current,the starch activated carbon at best performance presents excellent capacitance behaviour in 300 mg/g KOH aqueous electrolytes.