Polyindole coated NiCo 2 S 4 composites as high-performance supercapacitor electrode materials

NiCo 2 S 4 (NCS) and Polyindole (PIn) are two effective electrode materials used in energy storage systems. In this study, NCS@PIn hybrid structures were synthesized for the first time and the effects of PIn amount on the supercapacitor performance of NCS were evaluated. For this purpose, first, the PIn hollow microspheres were obtained by oxidative polymerization reaction. Then, the NCS was produced by a one-step hydrothermal synthesis approach and NCS@PIn composites in three different composition ratios were prepared by a simple ultrasonic mixing process. The NCS exhibited a specific areal capacitance value of 834.6 F g -1 at a current density of 1 A g -1 . The electrochemical performance of NCS was improved via a hybridization process. After composing NCS with 5 % PIn (NCS@PIn-5), the specific capacitance value reached up to 1442.8 F g -1 which was higher than those of PIn, NCS, and the other NCS@PIn hybrid electrodes. In addition, the NCS@PIn-5 coated electrode exhibited a charged retention of 94.7 % after 5000 cycles.