Water
splitting is a helpful way of converting renewable electricity
into fuel. The oxygen evolution reaction (OER) is a slow reaction
that provides low-cost electrons for water reduction reactions. Thus,
finding an efficient, low-cost, stable, and environmentally friendly
OER catalyst is critical for water splitting. Here, sodium cobalticarborane
(1) is introduced as a promising precatalyst for forming
an OER cobalt-based catalyst. The cobalt-based catalyst was characterized
by several methods and is suggested to be Co(III) (hydr)oxide. Using
fluorine-doped tin oxide, glassy carbon, platinum, and gold electrodes,
the OER activity of the cobalt-based precatalyst was investigated.
The overpotential for the onset of OER in the presence of 1 is 315 mV using fluorine-doped tin oxide electrodes. The onsets
of OERs in the presence of 1 using gold, platinum, and
glassy carbon electrodes in KOH solutions (1.0 M) turned out to be
275, 284, and 330 mV, respectively. The nanoparticles on the gold
electrodes exhibit significant OER activity with a Tafel slope of
63.8 mV/decade and an overpotential at 541 mV for 50 mA/cm2. In the case of the glassy carbon electrodes, a Tafel slope of 109.9
mV/decade and an overpotential of 548 mV for 10 mA/cm2 is
recorded for the catalyst. This paper outlines an interesting approach
to synthesize cobalt oxide for OER through a slow decomposition of
a precatalyst.