Abstract:
In this paper, we demonstrate excellent pseudo-capacitance behavior of nickelaluminum
double hydroxide microspheres (NiAl DHM) synthesized by a facile
solvothermal technique using tertbutanol as a structure-directing agent on nickel
foam-graphene (NF-G) current collector as compared to use of nickel foam current
collector alone. The structure and surface morphology were studied by X-ray
diffraction analysis, Raman spectroscopy and scanning and transmission electron
microscopies respectively. NF-G current collector was fabricated by chemical vapor
deposition followed by an ex situ coatingmethod of NiAlDHMactivematerial which
forms a composite electrode. The pseudocapacitive performance of the composite
electrode was investigated by cyclic voltammetry, constant charge–discharge and
electrochemical impedance spectroscopy measurements. The composite electrode
with the NF-G current collector exhibits an enhanced electrochemical performance
due to the presence of the conductive graphene layer on the nickel foam and gives a
specific capacitance of 1252 F g−1 at a current density of 1 A g−1 and a capacitive
retention of about 97% after 1000 charge–discharge cycles. This shows that these
composites are promising electrode materials for energy storage devices.
