Flower like cobalt-doped nickel oxide mesoporous microspheres for supercapacitor applications

Abstract

The flower-like NiO and Co-doped NiO mesoporous microspheres were successfully synthesized via hydrothermal method. The structural, morphological and electrochemical properties were studied. The X-ray diffraction analysis reveals the formation of cubic-structured NiO in both the samples. Pore size distribution spectrum confirms the mesoporous nature of the NiO and Co-doped NiO samples. Scanning electron microscopic images shows the formation of NiO and Co-doped NiO microspheres. The electrochemical nature of the NiO based samples were studied using cyclic voltammetric (CV), galvanostatic charge-discharge (GCD) and impedance analysis. The doping of Co enhances the electrochemical properties of NiO. GCD analysis exhibits the specific capacitance of 927 and 1052 Fg⁻¹ at 1 A g⁻¹ for NiO and Co doped NiO microspheres, respectively. The Co-doped NiO microspheres retained 100% of maximum capacitance even after 1000 cycles.