α-Fe_(2)O_(3)/炭纳米纤维电极材料的制备及其电化学性能分析

Preparation ofα-Fe_(2)O_(3)/carbon nanofiber electrode material and its electrochemical performance

采用电沉积技术将α-Fe_(2)O_(3)均匀负载在静电纺丝炭纳米纤维上,制备α-Fe_(2)O_(3)/炭纳米纤维复合材料。利用扫描电镜(SEM)、X射线衍射仪(XRD)以及物理吸附对复合材料进行形貌和结构分析,并通过恒电流充放电、循环伏安、交流阻抗技术考察其作为超级电容器电极材料的电化学性能。结果表明:α-Fe_(2)O_(3)/炭纳米纤维(α-Fe_(2)O_(3)/CNF-3)复合材料相比单纯炭纳米纤维(CNF)有着更丰富的介孔结构,有利于离子和电子的低电阻传输。同时,α-Fe_(2)O_(3)/CNF-3复合电极材料结合了双电层电容和赝电容的优良性能,在电流密度为1A/g下,电解液为6mol/L KOH时,其比电容值可达330.1F/g,是炭纳米纤维电极的3.76倍,并且经过8000次循环后仍能保持91.45%,具有较好的稳定性。

Theα-Fe_(2)O_(3) was uniformly loaded on electrospun carbon nanofibers(CNFs)using electrodeposition technique to prepareα-Fe_(2)O_(3)/carbon nanofiber(α-Fe_(2)O_(3)/CNF)composite material.The morphology and structure of the composites were analyzed by SEM,XRD and physisorption.The electrochemical properties of the composite material as supercapacitor electrode material were investigated by constant current charge-discharge,cyclic voltammetry,and AC impedance techniques.The results showed that theα-Fe_(2)O_(3)/carbon nanofiber(α-Fe_(2)O_(3)/CNF-3)composites had a richer mesoporous structure than pure CNF,which was favorable to the low resistance transmission of ions and electrons.Meanwhile,theα-Fe_(2)O_(3)/CNF-3 composite electrode material combined the excellent properties of double-layer capacitance and pseudocapacitance.At a current density of 1 A/g and an electrolyte of 6mol/L KOH,its specific capacitance value could reach 330.1F/g,which was 3.76 times higher than that of the carbon nanofibers electrode and could still maintain 91.45%after 8000 charging-discharging cycles,indicating good stability.