Nickel cobalt sulfide nanoparticles (NCS) embedded onto a nitrogen and sulfur dual doped graphene (NS-G) surface are successfully synthesized via a two-step facile hydrothermal process. The electrical double-layer capacitor of NS-G acts as a supporting host for the growth of pseudocapacitance NCS nanoparticles, thus enhancing the synergistic electrochemical performance. The specific capacitance values of 1420.2 F g-1 at 10 mV s-1 and 630.6 F g-1 at 1 A g-1 are achieved with an impressive capability rate of 76.6% preservation at 10 A g-1. Furthermore, the integrating NiCo2S4 nanoparticles embedding onto the NS-G surface also present a surprising improvement in the cycle performance, maintaining 110% retention after 10 000 cycles. Owing to the unique morphology an impressive energy density of 19.35 W h kg-1 at a power density of 235.0 W kg-1 suggests its potential application in high-performance supercapacitors.
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