Facile synthesis of layered MnWO₄/reduced graphene oxide for supercapacitor application

The layered MnWO₄/reduced graphene oxide (MnWO₄/RGO) was prepared through a facile one-pot low-temperature hydrothermal route without using any templates. The structure and morphology of MnWO₄/RGO nanocomposite were characterized through X-ray diffraction, Raman spectra, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption/desorption and thermo-gravimetric analysis. While its electrochemical behaviors were investigated using cyclic voltammograms, galvanostatic charge/discharge and electrochemical impedance spectroscopy. In the case of three electrode cells, MnWO₄/RGO with 7.28 wt% RGO content fulfilled a maximum specific capacitance of 288 F g⁻¹ at 5 mV s⁻¹ with the potential range from −0.35–0.55 V. While in the two electrode cell, it obtained a maximum specific capacitance of 109 F g⁻¹ at 5 mV s⁻¹ and displayed the cycle life of 14.9% capacitance decline after 6000 cycles. - Highlights: • The MnWO₄/RGO was first prepared through a facile hydrothermal route. • MnWO₄/RGO composite show much higher specific capacitances than pure MnWO₄. • The electrochemical properties of MnWO₄/RGO arise from the synergistic effect.