Electrospun NiMoO4-encapsulated carbon nanofibers electrodes for advanced supercapacitors

Abstract

NiMoO4-encapsulated carbon nanofiber (NiMoO4/ECNFs) composites have been synthesized successfully using electrospinning method and subsequent thermal treatments. The prepared specimens were examined using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), thermal gravimetric analyzer (TGA), and Fourier transform infrared spectroscopy (FTIR). Electrochemical measurements including cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) were performed on the symmetric supercapacitors (SSCs) which were assembled from the (75 %)NiMoO4/ECNFs binder-free nanostructured electrodes. Morphological and structural investigations revealed an open 3D interconnected conductive and grain-like texture with homogeneously dispersed monoclinic NiMoO4 nanoparticles. Moreover, a high specific capacity of 122.5 Fg−1 at 1 Ag−1 and an excellent energy density of 43.9 Whkg−1 at a power density of 1567.9 Wkg−1 were obtained from the SSCs. The constructed devices also delivered outstanding cyclic stability (92 % retention after 3000 cycles). The observed electrochemical properties have been ascribed to the uniform dispersion of nanoparticles in the conductive carbon nanofiber matrix. The results suggest that as-fabricated NiMoO4/ECNFs can be considered as a promising electrode material for high-performance supercapacitors.