M. Ramadan, A.M. Abdellah, S.G. Mohamed, N.K. Allam
The American University in Cairo,
Egypt
Keywords: supercapacitors, binder-free, nanofibers
Summary:
Rational design of binder-free materials with high cyclic stability and high conductivity is a great need for high-performance supercapacitors. We demonstrate a facile one-step synthesis method of binder-free MnO@C nanofibers as electrodes for supercapacitor applications. The topology of the fabricated nanofibers was investigated using FESEM and HRTEM. The X-ray photoelectron spectroscopy (XPS) and the X-ray diffraction (XRD) analyses confirm the formation of the MnO structure. The electrospun MnO@C electrodes achieve a high specific capacitance of 578 F/g at 1 A/g with an outstanding cycling performance. The electrodes also show 127% capacity increasing after 3000 cycles. An asymmetric supercapacitor composed of activated carbon as the negative electrode and MnO@C as the positive electrode shows an ultrahigh energy density of 35.5 Wh/kg with a power density of 10.7 kW/kg. The device shows a superior Columbic efficiency, cycle life, and capacity retention.