Highly porous NiMoO4 tailored onto amine functionalized CNT as advanced nanocomposite electrocatalyst for supercapacitor application

Abstract

In this study, the NiMoO4-carbon nanotubes (NiMoO4-CNTs) nanocomposite with interesting vertical nanosheet architecture and hierarchical mesoporous surface was synthesized via a simple hydrothermal treatment, followed by annealing process. The NiMoO4 nanoparticles were chemically tailored onto amine functionalized CNT through the reactive –NH2 group available; this noble electrode design not only resulted to remarkably high specific surface area of 181.88 m2 g−1 with numerous numbers of active sites, but also ensured outstanding mechanical and chemical stability that helped retained 91.93% capacity retention even after 5000 continuous cycles at fast scan rate. The fabricated NiMoO4-CNT electrode press deposited onto nickel foam substrate obtained specific capacitance of 611.69 F g−1 and 20.42 W h kg−1 energy density at 1 A g−1 current density. Furthermore, the annealing temperature was a critical factor during the synthesis of the modified material as it has direct effect on the structure and crystal phase, as well as to the amount of decomposed CNT; thus, the effect of using low and high annealing temperature towards the electrochemical activity of the modified material was extensively examined. The synthesized materials were investigated by using thermo gravimetric analysis, X-ray diffraction, field emission scanning electron micrographs equipped with energy dispersive X-ray spectrometer, and Brunauer–Emmett–Teller.