Investigation on two-dimensional molybdenum oxide-graphitic carbon nitride (MoO3-g-C3N4) heterostructures based hybrid electrodes for the fabrication of high energy density solid state supercapacitors

Abstract

BackgroundThe fabrication of high-performance supercapacitor electrodes has been extensively investigated for future high power storage applications. Molybdenum trioxide (MoO3) was synthesized and the graphitic carbon nitride have been introduced with the MoO3 to enhance the electrochemical performance by synergistic effect. MethodsMoO3-gC3N4 Nanocomposite (NC) was synthesized by thermal treatment followed by sonication process and can be utilized as active material for the preparation of supercapacitor electrode. The solid-state hybrid supercapacitor device (SHSC) is fabricated with MoO3-gC3N4 NC as cathode, activated carbon as anode, and 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4) ionic liquid as an ionogel electrolyte to perform the electrochemical studies. Significant findingsCyclic voltammetry (CV) revealed that the synthesized composite delivers higher specific capacity of 520. 97 C/g at 10 mV/s. The electrochemical impedance spectroscopy (EIS) of MoO3-g-C3N4 NC reveals lower solution (Rs) and charge transfer resistance (Rct) of 0.05 and 3.14 Ω respectively. The fabricated MoO3-g-C3N4//AC SHSC delivers high energy density of 59.75 Wh/kg and a high-power density of 1125 W/kg. Furthermore, the SHSC exhibits superior cyclic stability of 86.1% even after 6000 consecutive charge-discharge cycles.