摘要
以冷冻干燥获得的多孔胡萝卜为炭源,经过600℃氮气氛围下炭化和KOH活化,获得了多孔结构的炭材料。采用红外光谱、X-射线粉末衍射、扫描电镜、透射电镜、循环伏安、恒流充放电和交流阻抗对多孔炭进行了微结构和电容性能研究。结果表明:通过活化处理,多孔炭的比表面积从7 m2·g-1大幅提高到147 m2·g-1。而且,活化后的多孔炭产生了414 F·g-1的最大比电容,且电流增至4 A·g-1时的电容保持率为74.5%。而未活化的多孔炭最大电容为253 F·g-1,电容保持率仅为45.1%。此外,活化后的多孔炭还具有优异的电化学稳定性。在5 A·g-1电流下循环8 000圈后,其电容保持率高达94%。活化后的多孔炭在电容性能方面的极大改善与其比表面积的大幅提高及介孔的增多有密切关系。
Porous carbon materials were prepared from freeze-dried porous carrots as carbon sources through carbonization at 600 ℃ in nitrogen atmosphere, followed by KOH activation. The microstructures and capacitive properties of carbon materials were examined by FTIR, XRD, SEM, TEM, CV, CD and EIS. Electrochemical results indicated that, after being activated, porous carbon showed a significant improvement in specific surface area （from 7 m2·g-1 to 147 m2·g-1）. Moreover, activated carbon displayed a maximum specific capacitance of 414 F ·g-1. Even when the current increased to 4 A·g-1, its capacitance retention reached 74.5%. While non-activated carbon had only 253 F ·g-1 and 45.1% retention. Additionally, activated carbon exhibited high electrochemical stability with 94% retention after 8 000 cycles. The remarkable improvement in capacitive performance was strongly related to the significant improvement of specific surface area and the increase of mesopore.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2015年第11期2128-2134,共7页
Chinese Journal of Inorganic Chemistry
基金
新疆维吾尔自治区自然科学基金项目(No.2014211A015)资助项目
关键词
多孔胡萝卜
多孔炭
KOH活化
电容性能
porous carrots
porous carbon
KOH activation
capacitive properties
