Effect of different templating agents on cobalt ferrite (CoFe2O4) nanomaterials for high-performance supercapacitor

Cobalt ferrite (CoFe2O4) was successfully grown on the nickel foam by a mild hydrothermal method combined with a simple annealing treatment, utilizing SDS, PVP, CTAB, and PVA as template agents. The effect of different template agents on the morphology and electrochemical performance of CoFe2O4 electrode for supercapacitor was further investigated in detail. The physicochemical properties of the CoFe2O4 materials were examined via the X-ray diffraction, the N-2 adsorption-desorption, the scanning electron microscopy, and X-ray photoelectron spectroscopy. It can be proved that the purity of the material was high; the surface morphology and aperture were changed by using different template agents. In particular, the CoFe2O4 electrode, when adding an appropriate amount of PVA, SDS, PVP, and CTAB, showed a high capacitance of 1342, 828, 1100, and 1148 F g(-1) at 1 A g(-1). In addition, an asymmetric supercapacitor (ASC) was assembled using CFO-A as the positive electrode, activated carbon as the negative electrode, and 6 M KOH solution as the electrolyte. The ASC own an energy density of 55.42 Wh kg(-1) at a power density of 769.7 W kg(-1) and a retention rate of 56% at a current density of 10 A g(-1), which exhibits excellent performance.