Modification of the oxygen-containing functional group on activated carbon fiber in electrodes of an electric double-layer capacitor
Modification of the oxygen-containing functional group on activated carbon fiber in electrodes of an electric double-layer capacitor
复制标题
DOI：
10.1016/j.jpowsour.2005.10.061
复制
发表时间：
2006-08-25
影响因子：
9.2
通讯作者：
Morimoto, Tatsuya
中科院分区：
文献类型：
--
作者：
Oda, Hirokazu;Yamashita, Akira;Morimoto, Tatsuya
为了定量探讨活性炭纤维官能团对双电层特性的影响，采用氧化还原法制备了含有不同官能团量的活性炭纤维。用反滴定法和x射线光电子能谱法比较了两种方法中ACFs官能团的数量。在水电解质的情况下，电容量更多地取决于氧官能团而不是BET表面积。在正极和负极之间加入不同数量氧官能团的ACFs，最大可使电容量增加30%。认为官能团数量的增加不仅促进了电极的润湿性，而且使电极的负电荷增加，从而增加了容量。另一方面，在有机电解质的情况下，孔结构似乎比官能团是一个更主要的因素。同时，测试了电极在3万次充放电循环后的特性，以验证其在长周期运行中的可靠性。正极上的酚羟基明显增加。(c) 2005 Elsevier B.V.版权所有
In order to discuss quantitatively the effect of functional groups of activated carbon fibers (ACFs) on electric double-layer characteristics, ACFs with various amounts of functional groups were prepared from the same ACF by redox methods. The amount of functional groups of ACFs was compared between the method by back titration and by X-ray photoelectron spectroscopy (XPS). In the case of the aqueous electrolyte, the electric capacity depended more on oxygen functional groups than on BET surface area. At the greatest 30% of increase in electric capacity was obtained by using ACFs with different amount of oxygen functional groups between the positive electrode and the negative one. It was considered that a larger number of functional group promotes not only the wettability of electrodes but also the negative charge of electrodes leading to an increase in capacity. On the other hand, in the case of the organic electrolyte, pore structure seemed to be a more dominant factor than functional group. Also, the characteristics of the electrodes after 30,000-cycle charge-discharge were determined to confirm the reliability in an extended cycle operation. A significant increase in phenolic hydroxyl group was confirmed on the positive electrode. (c) 2005 Elsevier B.V. All rights reserved.