聚苯胺-石墨烯/聚酰亚胺复合导电纱的制备及其超电容特性

为了提高石墨烯/聚酰亚胺(rGO/PI)复合纱线电极的电化学性能,采用电化学聚合法在rGO/PI复合纱线表面沉积聚苯胺(PANI)颗粒,研究了沉积时间对PANI-rGO/PI复合导电纱的形貌及增重的影响。结果表明, PANI在rGO/PI复合纱线表面均匀沉积,且沉积量随着沉积时间的增加而增大。采用循环伏安法(CV)、恒流充放电法(GCD)研究了PANI-rGO/PI复合导电纱线的电化学行为。结果表明, PANI沉积时间对纱线电极的循环伏安特性、恒流充放电曲线等有很大的影响,当PANI沉积时间为900 s时,所得PANI-rGO/PI复合纱线电极的循环伏安特性和恒流充放电性能表现均最优,比电容为81.22 F·cm^-3,而rGO/PI纱线电极仅为16.4 F·cm^-3。以最优工艺制得的PANI-rGO/PI复合导电纱作为电极组装了纤维状超级电容器,采用交流阻抗谱法(EIS)、 CV及GCD对器件进行电化学性能表征。结果表明,该器件体积比电容可达41.73 F·cm^-3,在充放电3 000次后比电容依然能够维持在85%左右,所得纤维状超级电容器经过串联可成功驱动LED灯。

Preparation and supercapacitance characteristics of polyaniline-graphene/polyimide composite conductive yarn

In order to improve the electrochemical properties of graphene/polyimide (rGO/PI) composite yarn electrode, polyaniline (PANI) particles were deposited on the surface of rGO/PI composite yarn by electrochemical polymerization, and the effect of deposition time on the morphology and weight gain of PANI-rGO/PI composite conductive yarn was studied. As a result, PANI is deposited uniformly on the surface of the rGO/PI composite yarn, and the deposition amount increases with the deposition time increasing. The electrochemical behavior of PANI-rGO/PI composite conductive yarns was studied by cyclic voltammetry (CV) and galvanostatic discharge-charge method (GCD). The results show that the PANI deposition time has a great influence on CV and GCD characterastics. When the deposition time of PANI is 900s, the CV characteristics and GCD performance of the electrode of PANI-rGO/PI composite yarn are optimal, with a specific capacitance of 81.22 Fcm-3, while the electrode of rGO/PI yarn is only 16.4 Fcm-3. The PANI-rGO/PI composite conductive yarns with optimal process were assembled into a fiber-shaped supercapacitor, the electrochemical properties of the fiber-shaped supercapacitor were studied through the electrochemical impedance spectroscopy (EIS), CV and GCD. The results show that the volume specific capacitance of the device can reach 41.73 Fcm-3, and the device shows an excellent long-life performance up to 3000 times with a retention of~85%. The PANI-rGO/PI fiber-shaped supercapacitors can be readily connected in serial to power LED.