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The pursuit for renewable sources of energy has increased rapidly due to the continuous depletion of non-renewable sources. Supercapacitors have attracted considerable attention because they can store electrical energy. In this study, a hierarchical mesoporous carbon sphere@nickel cobalt sulfide (CS@Ni–Co-S) core–shell was synthesized using a facile hydrothermal method. The reaction involved green synthesis without further sulfurization or post-heat treatment. The CS@Ni–Co-S core–shell microstructures exhibited a high capacitance of 724.4 F g^− 1 at 2 A g^− 1 in a 6 M KOH electrolyte. Good specific retention of 86.1% and high Coulombic efficiency of 97.9% were obtained after 2000 charge–discharge cycles. High energy density (58.0 Wh kg^− 1 at 1440 W kg^− 1) and high power density (34.2 Wh kg^− 1 at 7200 W kg^− 1) were observed. Through this study, a cost-effective and simple synthesis of CS@Ni–Co …