Novel FeNi2S4/TMD-based ternary composites for supercapacitor applications

Ternary electrode materials based on graphene, FeNi2S4, and transition metal dichalcogenides (TMDs) were obtained via a one-pot synthesis method. Compared to binary materials, FeNi2S4 graphene (g)-2D-TMD nanocomposites exhibited better performance, which is a direct consequence of their unique ternary structures and the induced synergistic effect among their three components-ultrathin TMD nanosheets, highly conductive graphene networks, and FeNi2S4 nanoparticles. With the fabricated materials, we constructed electrodes to assess the electrochemical performance. The results are promising: the materials exhibited rapid electron and ion transport rates and large electroactive surface areas, testifying to their excellent electrochemical properties. In particular, the FeNi2S4-g-MoSe2 electrode demonstrated a maximum specific capacitance of 1700 F g(-1) at a current density of 2 A g(-1) (8.5 F cm(-2) at a current density of 10 mA cm(-2)) and a capacitance retention of approximately 106% after 4000 cycles at a charge discharge current density of 2 A g(-1). These electrochemical results indicate that the ternary composite, FeNi2S4-g-MoSe2, is a promising candidate electrode material for high-performance supercapacitors.