Optimised electrochemical energy storage performance of MoS₂ anchored to carbon cloth for advanced asymmetric aqueous supercapacitors

We explore the electrochemical energy storage performance of binder-free molybdenum disulphide decorated carbon cloth electrodes (MoS₂@CC) in six aqueous electrolytes, selecting the most suitable combination for the construction of an asymmetric supercapacitor. The MoS₂@CC electrodes were synthesised by a single-step hydrothermal method without the use of a binder. Our findings show that the capacitance performance and resilience of the MoS₂@CC electrodes are strongly influenced by the electrolyte, particularly the overall conductivity. Optimal performance, balancing capacitance, equivalent series resistance and cycle life was achieved in 1.0 M Na₂SO₄ in which MoS₂@CC delivers a capacitance of 223±2 F g⁻¹, retaining ≈94% capacity after 5000 charge–discharge cycles. In comparison, 0.5 M H₂SO₄, and 5.0 M LiCl, although initially outperforming 1.0 M Na₂SO₄, produced rapid electrode degradation. An asymmetric supercapacitor using binder-free MoS₂@CC and manganese oxide decorated carbon cloth (MnO₂@CC) electrodes in 1.0 M Na₂SO₄ electrolyte exhibited a capacitance of 55 ± 2 F g⁻¹, a specific energy density of 30.3 ± 0.4 W h kg⁻¹, and a power density of 625 ± 25 W kg⁻¹ over a 2.0 V voltage window comparable with, or superior to, similar devices reported in the literature. The asymmetric cell demonstrated excellent stability, retaining 82% capacitance after 5000 galvanostatic charge–discharge cycles and 80% after 15000 cycles.