静电纺丝PANI/CNT/PEO超级电容器电极的性能研究

Study on electrospinning fibrous electrodes made of PANI/CNT/PEO suspension for supercapacitors

采用静电纺丝制备高性能、薄膜纤维结构电极的超级电容器。制备了均匀对称的三明治式固态超级电容器,其电极为静电纺丝制备的聚苯胺、多壁碳纳米管、聚氧化乙烯薄膜结构,电解质为聚乙烯醇和硫酸。研究了静电纺丝参数对纤维直径的影响,通过改变纺丝距离和溶液流量可以获得微孔薄膜纤维电极。当纺丝距离从80 mm提高到140 mm,纤维的平均直径从3.22μm降低到1.40μm,相对应电极的比电容从70 F/g上升到95 F/g。用这种纤维结构电极制备的超级电容器表现出很好的循环稳定性,用平均纤维直径1.40μm的电极制作的超级电容器在1 000次充放电之后比电容仍能保持90%。

Electrospinning was used in the preparation of high performance, membrane-like electrodes for supercapacitors. The supercapacitors were assembled with two electrodes and gel electrolytes in a sandwich form. The electrodes were prepared by electrospinning polyaniline （PANI）/multiwalled carbon nanotube （MWCNT）/polyethylene oxide （PEO） compound suspension. The gel electrolyte consisted of polyvinyl alcohol（PVA）/sulfuric acid （H2SO4）. Effects of electrospinning parameters on the fiber diameter were studied. Results show that, higher stand-off distance combining with lower suspension flow rate can result in smaller diameter of the electrospun fibers. The average diameters of the fibers decrease from 3.22 μm to 1.40 μm and the corresponding specific capacitance of the electrodes increases from 70 F/g to 95 F/g when the stand-off distance ranges from 80 mm to 140 mm. The supercapacitors using fibrous electrodes in this work show good cyclic stability. The specific capacitance of the electrode with 1.40 μm average fibers diameter can retain 90% after 1 000 charge/discharge cycles.