| 초록 |
Electrochemical supercapacitors have been considered as promising energy storage devices due to their high power density and long cycle stability. The energy density (E) of the supercapacitors is usually limited by the operating voltage (V) according to the equation E = CV2/2 where C is the device capacitance. Asymmetric supercapacitors design is an effective method for extending the operating voltage window. In this study, we fabricated hybrid carbon nanofibers (CNFs) from polyimide (PI), poly(vinyl pyrrolidone) (PVP) and manganese dioxide (MnO2) via electrospinning, carbonization and dip-coating process, and investigated their microstructures and electrochemical properties as supercapacitor electrode materials. To extend the operating voltage window, asymmetric supercapacitors, which consist of PI/PVP/MnO2–based hybrid CNFs as positive electrode, neat PI-based CNFs as negative electrode, PI-based membrane separator, and PVA/H3PO4 electrolyte, were also fabricated and analyzed. |
