排序方式: 共有14条查询结果,搜索用时 0 毫秒
1.
The pore structures of two activated carbons from sawdust with KOH activation and coconut-shell with steam activation for supercapacitor were analyzed by N2 adsorption method. The electrochemical properties of both activated carbons in 6 mol/L KOH solution and 1 mol/L EtgNPF4/PC were compared, and the effect of pore structure on the capacitance was investigated by cyclic voltammetry, AC impedance and charge-discharge measurements. The results indicate that the capacitance mainly depends on effective surface area, but the power property mainly depends on mesoporosity. At low specific current (1 A/g), the maximum specific Capacitances of 276.3 F/g in aqueous system and 123.9 F/g in nonaqueous system can be obtained from sawdust activated carbon with a larger surface area of 1 808 m^2/g, butat a high specific current, the specific capacitance of coconut-shell activated carbon with a higher mesoporosity of 75.1% is more excellent. Activated carbon by KOH activation is fitter for aqueous system and that by steam activation is fitter for nonaqueous system. 相似文献
2.
3.
4.
磁流变液是近年来研究的热点,如今汽车线控技术的不断成熟和发展,利用传感器,控制元件,电子元件驾驶员动作转化为电信号,通过电线传递指令来操纵汽车,而不再需要传统的复杂的机械和液压连接装置.针对新型智能流体材料——磁流变液,我们将其应用于汽车线控制动系统中.利用磁流变液的这一特性设计出的制动器,再辅以合理的控制和信息反馈系统,可以实现制动力与地面附着力的快速匹配,甚至可以完成连续精准无脉动的ABS制动过程,从而代替传统液压机械式ABS,有利于实现底盘集成控制,大幅改善车辆制动性能. 相似文献
5.
6.
7.
Effect of activated carbon and electrolyte on electrochemical properties of organic supercapacitor was investigated. The results show that specific surface area and mesoporosity of activated carbon influence specific capacitance. If specific surface area is larger and mesoporosity is higher, the specific capacitance will become bigger. Specific surface area influences resistance of carbon electrode and consequently influences power property and pore size distribution. If specific surface area is smaller and mesoporosity is higher, the power property will become better. Ash influences leakage current and electrochemical cycling stability. If ash content is lower, the performance will become better. The properties of supercapacitor highly depend on the electrolyte. The compatibility of electrolyte and activated carbon is a determining factor of supercapacitor's working voltage. LiPF6/(EC+EMC+DMC) is inappropriate for double layer capacitor. MeEt3NPF4/PC has higher specific capacitance than Et4NPF4/PC because methyl's electronegativity value is lower than ethyl and MeEt3N^+ has more positive charges and stronger polarizability than Et4N^+ when an ethyl is substituted by methyl. 相似文献
8.
通过HNO3氧化和100~700℃不同温度热处理,在活性炭表面产生了不同含量的含氧官能团,用Boehm滴定法测定了官能团的含量和种类,用循环伏安、交流阻抗和恒流充放电方法调查了有机体系中含氧官能团对活性炭电容行为的影响。结果表明:较高的HNO3浓度氧化产生较多的热解产物为CO2的基团,热处理降低含氧官能团特别是羧基等热解产物为CO2的基团的含量。比电容与官能团总数没有关联,但与[酚羟基]+[羰基]-[羧基]-[内酯基]([X]表示X的含量)成正相关。氧化提高了比电容,但同时增加了内阻,500℃时热处理的试样获得最高比电容,从原始样的146 F/g增加到163 F/g。 相似文献
9.
10.