Synthesis of multiwall carbon nanotube wrapped Co(OH)2 flakes: A high-performance supercapacitor

Abstract The problem of poor electron conductivity is always associated with pseudocapacitive electrode material that deters full utilization of the active material. To have a viable solution to this problem, we report fabrication of a composite material bringing highly conductive carbon nanotube (CNT) wrapped pseudocapacitive with Co(OH) 2 nanoflakes. An in situ growth route evolves the supercapacitor via our laboratory developed modified hydrothermal reaction condition (MHT). An electrochemical investigation substantiates that the composite material electrode is highly active, which delivers a maximum specific capacitance of 603 F g −1 (at 1 mV s −1 scan rate), outstanding long-term cyclic stability with 96% retention at a constant current density of 1.5 A g −1 after 1000 cycles of operation. Thus it offers almost an effortless approach to fabricate high-power and high-energy density supercapacitors. By virtue of having high-capacity of pseudocapacitive hydroxides and desirable conductivity of carbon-based materials, the as-synthesized material could be a promising candidate for the development of supercapacitor electrode material.