MoSe2‐PANI Nanocomposite as Supercapacitor Electrode Material: Optimization, Mechanism and Electrochemical Performance

Abstract In this report, MoSe 2 ‐Polyaniline (PANI) nanocomposite with different amounts of MoSe 2 (0.05 g, 0.1 g and 0.2 g) were synthesized via in‐situ oxidative polymerization method. The morphology and wt % ratio of nanocomposites was studied using Field emission scanning electron microscopy (FESEM) and Energy dispersive X‐ray spectroscopy (EDX), respectively. Atomic and weight concentration of the nanocomposite was calculated using X‐ray Photoelectron Spectroscopy (XPS) and the results were in agreement with EDX analysis. The optimum nanocomposite as the electrode material for supercapacitor showed the highest specific capacitance of 463 F/g at a scan rate of 5 mV/s and retains ∼72 % specific capacitance after 3000 charge‐discharge cycles. The MoSe 2 ‐PANI nanocomposite attains an energy density of 19.6 Wh/kg at a power density of 12.7 W/kg. The enhancement in the electrochemical activity of the MoSe 2 ‐PANI electrode was achieved by using synergetic effects of electrical double‐layer capacitors (MoSe 2 nanosheets) and pseudocapacitors (Polyaniline nanofiber). MoSe 2 ‐PANI nanocomposite showed improved electron and ion transfer mechanism and improvement in the wettability of the electrode material. The thermogravimetric analysis (TGA) confirmed that the nanocomposite has improved thermal stability with mass loss of 28 %. The Brunauer‐Emmett‐Teller (BET) study confirm the high surface area (61.147 m 2 g −1 ) and pore volume (8.595 cm 3 g −1 ) as compared to their pristine samples. The outstanding electrochemical performance has proved that MoSe 2 ‐PANI nanocomposite has a great potential to be an electrode material in energy storage devices.