碳纤维/棉纤维/聚吡咯柔性复合材料的制备及性能研究

柔性超级电容器作为一种储能器件,具有功率密度高、充电时间短、循环寿命长、比电容高等优点,可满足可穿戴器件的需求,而柔性电极材料是决定柔性超级电容器发展的关键因素,它决定着电容器的主要性能指标。采用混纺的方法制备了碳纤维含量为20%(质量分数)的碳纤维/棉纤维混纺纱线,然后通过电化学沉积法在碳纤维/棉纤维混纺纱线上生长聚吡咯颗粒,成功制备了20%(质量分数)碳纤维/棉纤维/聚吡咯柔性复合材料。利用扫描电子显微镜、拉曼光谱分析仪和电化学工作站研究了复合材料的形貌、聚吡咯沉积情况以及复合材料的电容性能。结果表明,20%(质量分数)碳纤维/棉纤维/聚吡咯柔性复合材料中,聚吡咯颗粒直径为30~60 nm,且沉积均匀,化学活性较高;在1.02 mA/cm^2电流密度下,复合材料的最大比电容达到1.28 F/cm^2,其高比电容归因于电极的独特结构;复合材料具有良好的柔韧性、机械稳定性和充放电循环寿命,其经过6000次弯曲循环后,电容保持率仍有80%以上,可以用作柔性可穿戴超级电容器的电极材料。

Preparation and properties of carbon fiber/cotton fiber/polypyrrole flexible composites

Flexible supercapacitor,as a kind of energy storage device,has the advantages of high power density,short charging time,long cycle life and high specific capacitance,which can meet the needs of wearable devices.Flexible electrode material is the key factor determining the development of flexible supercapacitor,anddetermines the main performance indicators of capacitors.Carbon fiber/cotton fiber blended yarn with 20wt%carbon fiber content was prepared by blending method.Polypyrrole particles were grown on carbon fiber/cotton fiber blended yarn by electrochemical deposition method,and 20wt%carbon fiber/cotton fiber/polypyrroleflexible composite was successfully prepared.The morphology,polypyrrole deposition and capacitance properties of the composites were studied by scanning electron microscopy,Raman spectroscopy and electrochemical workstation.The results showed that in 20wt%carbon fiber/cotton fiber/polypyrrole flexible composites,the diameter of polypyrrole particles was 30-60 nm,the deposition was uniform and the chemical activity is high.At 1.02 mA/cm^2 current density,the maximum specific capacitance of the composites reached 1.28 F/cm^2,and its high specific capacitance was attributed to the unique structure of the electrode.The composite materials had good flexibility,mechanical stability and charge-discharge cycle life.After 6,000 bending cycles,the capacitance retention rate was still over 80%.It could be used as an electrode material for flexible wearable supercapacitors.