NI-CO AND ZN-CO BIMETALLIC DECORATED MULTI WALLED CARBON NANOTUBE NANOCOMPOSITE AS SUPERCAPACITOR ELECTRODE

Abstract

This study investigates the structural, morphological, optical, and electrochemical properties of polyaniline (PANI)-based nanocomposites doped with nickel oxide (NiO) and zinc oxide (ZnO). X-ray diffraction (XRD) analysis confirms the successful formation of PANI/NiO and PANI/ZnO nanocomposites with reduced crystallinity of metal oxides and improved phase of PANI, which enhances electrochemical performance. Fourier-transform infrared spectroscopy (FTIR) reveals characteristic absorption bands indicating strong interactions between PANI and metal oxides. Scanning electron microscopy (SEM) shows a fibrous PANI structure interlaced with NiO nanoparticles, forming a porous network that facilitates rapid ion diffusion and charge transfer. UV–Vis spectroscopy highlights electronic interactions between PANI and metal oxides, with optical band gaps of 4.27 eV (PANI/NiO) and 4.13 eV (PANI/ZnO). Electrochemical analysis demonstrates superior pseudocapacitive behavior of the PANI/NiO nanocomposite, achieving a high specific capacitance of 1005 F/g at 5 mV/s in 2.0 M KOH electrolyte. The composite retains 85% of its initial capacitance at 50 mV/s, showcasing excellent rate capability and cycling stability. These findings underscore the potential of PANI/NiO nanocomposites as high-performance electrode materials for supercapacitor applications.