Abstract:
A simple wet chemical route involving ultrasonication is used in this work for the insitu
decoration of NiCo2O4 on the surface of carbon. The NPs of NiCo2O4 are synthesized via
same route. Nickel acetate tetra-hydrate and cobalt acetate tetra-hydrate are used as metal
precursors. MWCNTs counts for the carbonaceous moiety in the resulting hybrid of the
two materials. Polyethylene glycol (PEG 6000) is used as a capping agent along with
dimethyl formamide as solvent for the synthesis process. The morphology of the NPs is
examined through scanning electron microscopy. The capping agent successfully capped
the NPs size in an average diameter of 23 nm. The crystal structure of the resulting NPs
and composite is characterized by X-ray diffraction (XRD). Formation of a cubic
structure of NiCo2O4 is confirmed. Elemental analysis of the materials is performed via
EDS to investigate the percent weight of constituent elements in both NiCo2O4 NPs and
its nanocomposite with carbon. The electrochemical analysis of the materials is done via
cyclic voltammetry and galvanostatic charge discharge tests. A typical three electrode
system is used for the electrochemical measurement in a 2 M KOH electrolyte. A high
specific capacitance of 1788 F/g is obtained for the composite of NiCo2O4@MWCNTs.
The specific capacitance of NPs of NiCo2O4 is found to be 1442 F/g. cyclic stability test
conducted revealed that the composite material retain 96 % of the performance after 1000
cycles of charge discharge. The NiCo2O4 @NPs retained an efficiency of 89 % after 1000
charge discharge cycles.
