Superdispersed NiCo2S4 nanoparticles anchored on layered C3N4 for high performance supercapacitor

Abstract

In recent years, the concept of sustainable development has encouraged the development and application of green, natural, and recyclable energy storage devices. Herein, using Ni(NO3)20.6 H2O and Co(NO3)20.6 H2O as raw material and K2S2O8 as a vulcanizing agent, NiCo2S4 nanomaterials@C3N4 (NCS@C3N4) composite was prepared by a one-step solvothermal method, in which the introduction of C3N4 significantly improves the dispersion of NCS, while the petal-like NCS also expands the layer spacing of C3N4, which effectively alleviates the structural instability and promotes the exposure of stable active sites during charge and discharge. Physical structure and electrochemical characterizations showed that the NCS were distributed on the surface of the C3N4 nanosheets, which reduced the stacking of the nanosheets and accelerated the charge transfer during the charging and discharging process. The specific capacity (Csp) of the NCS@C3N4 composite electrode was up to 890.4 C/g at a current density of 1 A/g. In addition, the supercapacitor consisting of NCS@C3N4 composite electrode had good cycling stability and still displayed excellent capacitance retention after 3000 cycles. The NCS@C3N4 composite greatly optimizes the stability and extends the operating life of supercapacitors, which has a broad application potential in the field of energy storage devices.