Polyaniline-wrapped 1D CoMoO4·0.75H2O nanorods as electrode materials for supercapacitor energy storage applications

Abstract

In this study, a simple and cost effective one-pot hydrothermal process has been carried out for the synthesis of 1D CoMoO₄·0.75H₂O nanorods. A binary composite of CoMoO₄·0.75H₂O/PANI has also been synthesized by the in situ oxidative polymerization of aniline with virgin CoMoO₄·0.75H₂O. Two types of PANI morphologies have been demonstrated: amorphous nanodimensional PANI uniformly coated on CoMoO₄·0.75H₂O nanorods, and interconnected hollow spheres like PANI inside the bulk material. The prepared CoMoO₄·0.75H₂O/PANI composite was characterized by X-ray diffraction analysis and Fourier transform infrared spectroscopy for the phase and formation, respectively. The surface morphology was investigated by using FESEM and TEM, which revealed the formation of the CoMoO₄·0.75H₂O/PANI composite. The electrochemical characterization of the pseudocapacitive CoMoO₄·0.75H₂O and CoMoO₄·0.75H₂O/PANI composites in 1 M Na₂SO₄ showed the highest specific capacitances of 285 F g⁻¹ and 380 F g⁻¹, respectively, at a current density of 1 A g⁻¹. The cyclic stability test demonstrated the specific capacitance retention of about 90.4% after 1000 consecutive charge–discharge cycles at a constant current density of 1 A g⁻¹, which is also higher than that of virgin CoMoO₄·0.75H₂O—86.3% retention of specific capacitance.