NiO nanoparticles/graphene nanocomposite as high-performance pseudocapacitor electrodes: Design and implementation

Abstract

A simple hydrothermal approach was used to successfully fabricate NiO/G nanocomposites. Since the addition of nickel oxide nanoparticles (NiO) to graphene instead of conducting polymeric materials produces better capacitances and improved capacity retention. Graphene-based inorganic composites have been attracting more and more attention. The as prepared NiO/G nanocomposite is characterized by XRD, TEM, Raman, XPS and nitrogen adsorption/desorption. It is demonstrated that NiO nanoparticles adorn graphene sheets to generate hierarchical nanostructures with rich porosity (33.8 nm) and substantial specific surface area (51 m2 g−1). Electrochemical characterization demonstrate that the mesoporous graphene/NiO can deliver a specific capacitance of 632 F g−1 at a current density of 2 Ag−1 and have a capacitance retention of 99.7% at 2Ag−1 after 6000 continuous charge–discharge cycles. In addition, the ASC constructed from NiO/G shows excellent energy density (30.56 Whkg−1), excellent power density (2800 Wkg−1) and impressive cycle performance (capacitance retention after 6000 cycles is approximately 92.7%). This strategy aids in the fabrication and utilization of hybrid nanocomposite in high-geared reversible supercapacitors.