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Copper-based transition metal sulfides are regarded as good supercapacitor electrode materials due to their cost-effectiveness and considerable theoretical capacity. However, their cycle stability, energy density and rate performance need to be improved. Herein, cobalt-doped Cu7S4(Co-Cu7S4) nanorods are synthesized at room temperature using environment-friendly routes of co-precipitation and self-sacrifice template processes. Results obtained from electrochemical characterizations and density functional theory calculations can prove the excellent doping kinetics and ideal electrochemical behavior of cobalt ions. Impressively, a high specific capacity of 1302.0 C g−1(2367.3 F g-1) at 4 A g−1and rate capabilities of 90.0 % at 10 A g−1and 61.8 % at 40 A g−1are obtained. The assembled hybrid supercapacitor (Co-Cu7S4//Active carbon) exhibited superior cycle stability with no insignificant decay after 40,000 charge/discharge process at 5 A g−1and 20 A g−1, and a maximum power density of 20.4 kW kg−1at 17.6 Wh kg−1. These excellent electrochemical properties can be ascribed to the porous nanostructures formed by shrinkage during the sulfide process, the rapid electrochemical kinetics, as well as the synergistic effect due to the cobalt ions. This study can provide useful insight into the design and development of electrode materials for high-performance energy storage devices.

•Ultrafine Mn3O4nanowires with a diameter of 4.0 nm were synthesized using a facile colloidal method.•Mn3O4nanowires show a large surface area of 175.1 m2g−1and a large pore volume of 0.7960 cm3g−1•Mn3O4nanowire electrode exhibit a predominant surface capacitive behavior, and shows a wide potential window of -0.5∼1.1V and high specific capacitance of 433.1 F g-1at 0.5 A g-1•Mn3O4nanowires//active carbon device shows a high energy density of 26.68 Wh kg-1at a power density of 442 W kg-1.