Synthesis and electrochemical behavior of nanostructured cauliflower-shape Co–Ni/Co–Ni oxides composites

Nanostructured Co–Ni/Co–Ni oxides were electrochemically deposited onto stainless steel electrode by electrochemical method and characterized for their structural and supercapacitive properties. The SEM images indicated that the obtained Co–Ni/Co–Ni oxides had cauliflower-type nanostructure. The X-ray diffraction pattern showed the formation of Co3O4, NiO, Co and Ni. The EDX elemental mapping images indicated that Ni, Co and O are distributed uniformly. The deposited Co–Ni/Co–Ni oxides showed good supercapacitive characteristics with a specific capacitance of 331 F/g at 1 mA/cm2 current density in 1 M KOH electrolyte. A mechanism of the formation of cauliflower-shape Co–Ni/Co–Ni oxides was proposed. A variety of promising applications in the fields such as energy storage devices and sensors can be envisioned from Co–Ni/Co–Ni oxides.