The effect of CoS components on the electrochemical and physical–chemical properties of porous CoS–Co3FeS8 heterogeneous nanosheets

Abstract

Transition metal sulfide compounds have attracted significant interest for use as supercapacitor electrodes owing to their distinct crystalline configurations and exceptional conductive properties, which facilitate rapid electron transfer and thereby improve overall energy storage performance. Among them, CoS exhibits ideal electrochemical performance in supercapacitors, offering high capacitance and good cycling stability. A novel composite material is synthesized in this work via a single-step hydrothermal procedure directly on a carbon cloth substrate. This process yields hexagonal nanosheets with a CoS–Co₃FeS₈ hybrid structure. The inclusion of the CoS phase significantly enhances the electrochemical properties of the Co₃FeS₈ component. This synergistic composite architecture greatly promotes more efficient electron transport and provides an enhanced active surface area, leading to superior overall performance. Furthermore, at a current density of 1 A g⁻¹, the asymmetric supercapacitor device (CSFCC) shows a specific capacitance of 123.2 F g⁻¹, an energy density of 33.5 Wh kg⁻¹ and a power density of 349.6 W kg⁻¹. Then, after 10 000 cycles, it retains 64.5% of capacitance, demonstrating stability. These findings show that the one-step hydrothermal synthesis method of binary sulfide composites is an effective method for preparing multi-component sulfide-based materials.