Free-standing and binder-free Molybdenum bisulfide nanospheres/reduced graphene oxide composite paper as flexible electrode for symmetric supercapacitor

A binder-free and self-standing Molybdenum bisulfide (MoS2) nanospheres/reduced graphene oxide paper has been successfully fabricated in this study. The composite papers were assembled into a flexible symmetric capacitor with relatively high specific capacitance and energy density. The capacitance of device is 323 F g(-1) at the current density of 0.2 A g(-1) with the maximum energy density of 44.9 Wh kg(-1). The retention rate of 76.8% is obtained at 500th cycle. With bending of the device, the capacitance of 277 F g(-1) can still be maintained with the retention rate of 73.7% in 500th cycle and the energy density of 38.5 Wh kg(-1).