Sponge-like Ni(OH)2–NiF2 composite film with excellent electrochemical performance

Abstract

Sponge-like porous Ni(OH)₂–NiF₂ composite (PNC) film was successfully synthesized by the anodization of nickel in a NH₄F and H₃PO₄ containing electrolyte. Thanks to the good conductivity and the highly porous architecture, PNC exhibited not only a high specific capacitance, but also a superior rate capability and a good cyclability (2090 F g⁻¹ at 10 mV s⁻¹, capacitance >1200 F g⁻¹ at 100 A g⁻¹ after 2000 cycles). Anodization of nickel is proven to be fast and facile and can be easily scaled up. The method described here is promising for the fabrication of supercapacitor electrodes with excellent performance.