Facile synthesis of MnCO3 nanoparticles on Ni foam for binder-free supercapacitor electrodes

Abstract

Rhombohedral MnCO3 nanoparticles were successfully grown on nickel foam via a facile and one-pot water-bath means, wherein the hydrolyzation of urea supplied alkali and carbonate ions. The structure and morphology of the nanocomposites were investigated by XRD, FIB/SEM and elemental mapping. Microscopic investigations revealed MnCO3 particles with mean sizes that varied from 110-255 nm. EDS mapping showed a homogeneous distribution of manganese, carbon and oxygen. The electrochemical properties of the produced composites were estimated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) measurements using 6 M KOH as the electrolyte. The resulting electrodes displayed maximum specific capacitance (163.7 F g-1 at 0.5 A g-1), respectable rate capability, and excellent long-term cycling life (91% retention after 1000 cycles). In addition, this manuscript offers us a simple and rapid strategy for the fabrication of electrode materials for use as energy storage devices.