LAUSR

Abstract The disadvantages that prevent supercapacitors from swapping batteries in most of the applications are linear discharge voltage, low specific energy, and high cost. Here, we report the fabrication of a new nanocomposite electrode by strategically combining ferrous tungstate and functionalized multiwalled carbon nanotubes (FeO4W/f-MWCNTs) hydrothermally for high-performance supercapacitors. This supercapacitor electrode shows specific capacitance as high as 875 Fg−1. The cycle tests show capacitance retention of 89.17% after huge 10,000 cycles in three electrode system. Further, a symmetric supercapacitor device made of FeO4W/f-MWCNTs delivers a high specific capacitance with good capacitance retention. Such a discovery of a novel electrode certainly paves way for the development of advanced nanocomposite electrodes for energy storage applications with substantial improvement in charge time, specific power, cycle life, and safety. Analytical techniques such as ultraviolet–visible spectroscopy and Fourier transform infrared spectroscopy confirm the presence of functionalities in the composite, whereas thermogravimetric analysis of the nanocomposite reveal better thermal stability compared to its counterparts. The crystallinity of the composite is ascertained by X-ray diffraction technique. The interplanner spacing (dhkl) in the nanomaterial is measured from high-resolution transmission electron microscopy and selected area electron diffraction methods. Energy-dispersive X-ray analysis is used for elemental analysis.