Hybrid ZnCo2O4@Co3S4 Nanowires for High-Performance Asymmetric Supercapacitors

Abstract

We successfully fabricate hierarchical ZnCo2O4@Co3S4 nanowires directly supported on nickel foam by a facile hydrothermal route. The as-synthesized product possesses large specific surface area and short reaction path, which result in superior electrochemical performances as the electrode of supercapacitor (SC). The obtained electrode material shows high area capacitance of 2.02 C g-1 at current density of 0.8 A g-1 with 95.3% retention of initial capacitance after 6000 cycles. Moreover, the assembled asymmetric supercapacitor (ASC) device using ZnCo2O4@Co3S4 nanowires as anode material displays noticeable electrochemical capability with an energy density of 79.8 mW h g-1 at power density of 1795 W kg-1 and 73.2 mW h g-1 at 9760 W kg-1. In addition, the device shows remarkable cycling capability, maintaining 82.2% retention after long-term cycles. It reveals the as-fabricated material would be promising energy storage materials.