花生壳制备微孔炭及其在电化学超级电容器中的应用

以未使用和使用氢氧化钠溶液处理的花生壳为碳源分别制备出微孔炭PSC-1和PSC-2.PSC-1和PSC-2的比表面积分别为552和726m2·g-1,其主要孔径都约为0.8nm.用PSC-1和PSC-2制备的电极和对称型超级电容器的循环伏安曲线均接近矩形,表明其具有良好的电容特性.在以微孔炭电极为工作电极、铂电极为对电极和银/氯化银电极为参比电极组成的三电极体系测量表明,在0.1A·g-1的电流密度下,PSC-1和PSC-2的比电容达到233和378F·g-1.经过1000次恒电流充放电循环后,在三电极体系和超级电容器中电极均表现出良好的稳定性和电容保持率.基于实验结果探讨了微孔炭的形成机理及其结构与电化学性质之间的联系.

Preparation and Characterization of Peanut Shell-Based Microporous Carbons as Electrode Materials for Supercapacitors

Microporous carbons (PSC-1 and PSC-2) were obtained directly by the carbonization of peanut shells without and with NaOH solution pretreatment, respectively. Both samples have a main pore voltammograms (CVs) of the PSC-1 and PSC-2 electrodes and the symmetrical supercapacitors show almost rectangular shape indicating excellent capacitance features. The specific capacitances of PSC-1 system using porous carbon as the working electrode, a platinum electrode as the counter electrode and a Ag/AgCl electrode as the reference electrode. Furthermore, the electrodes in both three-electrode systems and supercapacitors show high stability and capacitance retainability after 1000 cycles. The formation mechanisms for the two microporous carbons and the relationship between the carbon materials and their electrochemical properties are discussed based on the experimental results.