Transition molybdenum oxides (MoO3) and conductive polymer (polyaniline, PANI) nanomaterials were fabricated and asymmetric supercapacitor (ASC) was assembled with MoO3 nanobelts as negative electrode and PANI nanofibers as a positive electrode. Branched PANI nanofibers with a diameter of 100 nm were electrodeposited on Ti mesh substrate and MoO3 nanobelts with width of 30-700 nm were obtained by the hydrothermal reaction method in an autoclave. Redox active electrolyte containing 0.1 M Fe2+/3+ redox couple was adopted in order to enhance the electrochemical performance of the electrode nano-materials. As a result, the PANI electrode shows a great capacitance of 3330 F g-1 at 1 A g-1 in 0.1 M Fe2+/3+/0.5 M H2SO4 electrolyte. The as-assembled ASC achieved a great energy density of 54 Wh kg-1 at power density of 900 W kg-1. In addition, it displayed significant cycle stability and its capacitance even increased to 109% of the original value after 1000 charge-discharge cycles. The superior performance of the capacitors indicates their promising application as energy storage devices.
Keywords: MoO3 nanobelt; asymmetric supercapacitor; electro-deposition; polyaniline nanofiber; redox active electrolyte.