The current collector has played a vital role in energy storage devices. However, the application of conventional current collectors is seriously hindered by their inherent characteristics of limited loading surface area. High specific surface area current collectors with high conductivity, three-dimensional (3D) structure and convenient preparation are believed to be the most suitable alternatives to build high-property supercapacitors. Herein, chemical vapor deposition was applied to prepare a 3D, high surface area nickel foam@carbon fibers (NF@CFs) current collector for supercapacitors. The supercapacitor electrode integrated by 3D NF@CFs and high active MnO2 (MnO2/NF@CFs) delivered a considerable areal capacitance of 12.20 F/cm2 under a current density of 1 mA/cm2, and the capacitance retained 86.1% of its initial value even after 2000 charging and discharging cycles, demonstrating the exceptional cyclic stability. Moreover, the symmetric supercapacitor assembled with MnO2/NF@CFs-40 attained a capacitance as high as 5.64 F/cm2 at 1 mA/cm2 and with a power density of 0.225 mW/cm2, the corresponding energy density of 0.159 mW h/cm2 could be acquired.
Yang et al. (Sun,) studied this question.