High-performance three-dimensional nanoporous NiO film as a supercapacitor electrode

A three-dimensional nanoporous NiO film was fabricated using a two-step process through an electrochemical route. The as-prepared NiO film exhibited a highly nanoporous structure and high surface area (264 m2 g−1). The textural characterization of the film and its electrochemical performance as an electrochemical electrode were investigated. The electrode showed a high specific capacitance (1776 F g−1), power density (89 Wh kg−1), and energy density (16.5 kW kg−1). In addition, the electrode exhibited high and stable specific capacitance retention after a long cycle test in KOH solution. More importantly, the power density met the power requirements of the Partnership for a New Generation of Vehicles (PNGV).