A robust free-standing MoS2/poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) film for supercapacitor applications

Two-dimensional molybdenum disulfide (MoS2) is a promising energy storage material due to its high surface area and unique electronic structure. Free-standing flexible MoS2-based electrode is of importance for use in flexible energy storage devices, whereas there are limited reports available. In this work we developed a robust hybrid film, MoS2 incorporated with highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). This free-standing film possesses excellent mechanical properties with a fracture strength of 18.0 MPa and a Young's modulus of 2.0 GPa. It can deliver a large volumetric capacitance of 141.4 F cm-3, a high volumetric energy density of 4.9 mWh cm-3, and a capacitance retention rate of 98.6% after 5000 charge/discharge cycles. This film has demonstrated its application in an all-solid-state bendable supercapacitor as well.