静电溶液喷射纺丝制备蜂窝多孔碳纳米纤维及其超级电容器性能

Preparation of honeycomb porous carbon nanofibers via electro-blowing spinning and investigation of their supercapacitor performance

一维多孔碳纳米纤维具有比表面积高、长径比大、电子传输高效等特点,成为超级电容器电极材料的热门选择。利用静电溶液喷射纺丝技术,以聚乙烯吡咯烷酮(PVP)为成碳高聚物,聚四氟乙烯乳液(PTFE)为制孔剂,结合高温碳化工艺得到蜂窝多孔碳纳米纤维超级电容器电极材料。通过SEM、TEM、Raman、XRD和BET等测试对制备的电极材料形貌和结构进行了表征,并分析了制孔剂含量对纤维形貌、孔结构及电化学性能的影响。结果表明:当纺丝液中PVP∶PTFE质量比为1∶10时,制备的电极材料具有最大的比表面积165 m2/g;在0.5 A·g^(-1)电流密度下,其比电容值高达277.5 F·g^(-1);在二电极体系中,其功率密度为250 W/kg时,能量密度可达31.6 W·h/kg;经10000圈充放电循环后,其电容保持率可达98.4%,展示出了良好的电容性能和循环性能。这种独特的高孔隙率蜂窝多孔碳纳米纤维电极材料能够为电荷存储提供充足的活性位点,同时为电子/离子的快速传输提供便利通道,对高性能超级电容器电极材料的开发具有一定参考和指导意义。

One-dimensional porous carbon nanofibers have become a popular choice for supercapacitor electrode materials due to their high specific surface area,large aspect ratio,and efficient electron transport.In this study,honeycomb porous carbon nanofibers were synthesized using electrospinning technique,where polyvinylpyrrolidone(PVP)served as the carbon precursor and polytetrafluoroethylene(PTFE)emulsion acted as the pore-forming agent,followed by a high-temperature carbonization process.The morphology and structure of the prepared electrode materials were characterized using SEM,TEM,Raman spectroscopy,XRD,and Brunauer-Emmett-Teller(BET)analysis.Furthermore,the influence of pore-forming agent content on the fiber morphology,pore structure,and electrochemical performance was investigated.The results reveal that when the mass ratio of PVP∶PTFE in the spinning solution is 1∶10,the resulting electrode material exhibites the maximum specific surface area of 165 m²/g.Moreover,at a current density of 0.5 A·g^(-1),it achieves a high specific capacitance of 277.5 F·g^(-1).In a two-electrode system,the power density reaches 250 W/kg,resulting in an energy density of 31.6 W·h/kg.Additionally,after 10000 charge-discharge cycles,the capacitance retention remains as high as 98.4%,indicating excellent capacitive and cycling performance of the fabricated electrode material.Such a unique porous carbon nanofibers electrode material with its high porosity and honeycomb-like structure can offer abundant active sites for charge storage and provide convenient pathways for fast electron/ion transport,which holds significant reference and guidance for the development of high-performance supercapacitor electrode materials.