Chemical vapor deposition-based synthesis of binder-free nanostructure α-MoO₃ electrode material for PES devices

Abstract

Molybdenum-based metal oxides have succeeded in incredible consideration for supercapacitor applications due to their outstanding structural, morphological and electrochemical properties. Herein, a highly porous orthorhombic MoO3 (α-MoO3) nanobenzene like nanosheets are synthesized on nickel foam (Ni-F) via a simple and cost-effective chemical vapor deposition (CVD) technique. The x-ray diffraction (XRD) analysis confirmed the synthesis of nanostructured α-MoO3 having multi oriented diffraction planes. The surface morphology (SEM) analysis indicated that the entwined nanobenzene through nano-rods/particles is beneficial for good electrical conductivity hence the high electrochemical performance of synthesized α-MoO3. The electrochemical properties of synthesized α-MoO3 electrode material like cyclic voltammetry (CV), galvanostatic charging-discharging (GCD) and electrochemical impedance spectroscopy (EIS) are analyzed using a three-electrode electrochemical workstation in 2 M KOH electrolyte solution. The synthesized α-MoO3 pseudocapacitor presented a maximum specific capacitance of 3206 F/g at a current density of 1 A/g. Moreover, α-MoO3 exhibits a cyclic stability of about 99.95% after 3000 cycles, high energy density (111 Wh/kg), power density (2500 W/kg) and negligible charge transfer resistance (0.6 ohms), indicating that it can serve as an excellent electrode material for supercapacitors. The Power law and Dunn’s model simulations also confirmed that the excellent electrochemical performance of synthesized α-MoO3 electrode material is contributed by capacitive as well as diffusion-controlled behavior.