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Abstract
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Efficient low-cost electrocatalysts in the oxygen evolution reaction (OER) are important
components of renewable energy technologies, e.g. solar fuel synthesis and water splitting
for powering fuel cells. A great deal of attention has been attracted toward LDHs due to
their electrical power and they are potentially applied in the field of electrocatalysts. The
present paper reports synthesis of the Ni-Fe-Molybdate and Ni-Fe-Vanadate layered double
hydroxides (LDHs) using a simple co-precipitation method. Powder X-ray diffraction,
Fourier transform infrared spectra, Transmission electron microscopy, and X-ray energy
dispersive spectroscopy spectrum provide successful intercalation of the Vanadate and
Molybdate anions. Compared to the bare glassy carbon electrode, in alkaline media, the asobtained
Ni-Fe-MoO4-LDH represents superior electrocatalytic activity toward water
oxidation with the overpotential of 491 mV at10 mA/cm2 and a low Tafel slope of 23 mV/
dec. NieFe-MoO4-LDH exhibits good OER activity, which is stated as low onset overpotential,
small Tafel slope, and large exchange current density. The current density of the
NieFe-MoO4-LDH nanosheets is about 10 mA cm2 at the overpotential of 0.491 (V vs SCE).
This value is much larger than that of the NieFe-NO3-LDH and NieFe-VO3-LDH
nanoparticles.
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