Electrode materials with excellent performance are the basis for designing supercapacitors with outstanding stability and high specific capacitance. In this work, we prepared a type of ZnCo2O4 nanosheet structure with Ag nanoparticles through a multi-step hydrothermal strategy. The as-fabricated composite presented a specific capacity of 2540 F g-1 at 1 A g-1 due to the synergetic effect of its components and structure. The three-dimensional structure enabled the material to maintain an initial specific capacitance of 92.5% after 10 000 cycles. The asymmetric supercapacitor delivered an energy density of 72.36 W h kg-1 at a power density of 10 800 W kg-1. Moreover, it demonstrated 89% capacitance retention at 5 A g-1 after 10 000 cycles even when the operating temperature decreased to 0 °C.
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