Preparation and Properties of NiO/AC Asymmetric Capacitor

The nickel oxide nanoparticles were prepared by chemical bath deposition method with NiSO4 as raw materials and NH3H2O as precipitation agent. The crystal phase, microstructure and morphology of the nickel ox- ide were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), thermo gravimetric analyzer (TGA) and physical adsorption instrument. The results show that the product is porous spherical like particles with diameter of about 200 nm. Specific surface area of the nickel ox- ide heat-treated at 300℃ reaches 132 m 2 /g, with average diameter of 7.3 nm. The asymmetric capacitor with acti- vated carbon as negative electrode and nickel oxide as positive electrode shows good performance and cycling sta- bility. At the discharge current density of 25 mA/g, the asymmetric capacitor's specific capacitance can reach 1039 F/g, and its' charge-discharge efficiency is above 98%.