Novel dealloying-fabricated NiCo2S4 nanoparticles with excellent cycling performance for supercapacitors

In this work, NiCo(2)S(4 )nanoparticles for supercapacitors are successfully synthesized with a top-down strategy, using a novel dealloying method with an ion exchange reaction. The surface morphology and x-ray diffraction investigations demonstrated that NiCo2S4 nanoparticles are interconnected by ligaments of the synthesized sample. The dealloyed NiCo2S4 shows an enhanced electrochemical performance of about 1132.5 F g(-1) at 0.5 A g(-1); kinetic analysis implies a surface-controlled contribution from NiCo2S4 (53.86% capacitive contributions). Notably, the NiCo2S4//AC (active carbon) device displays a comparatively high energy density (22.83 Wh kg(-1)), maximum power density (1327.1 W kg (-1)) and superior cycling performance (capacitance retention of 108% after 30 000 cycles).