The biggest problem with platinum group electrocatalysts is that they are extremely
expensive and their annual production is small, as their content in the Earth's crust is very
low and localized. For these reasons, the goal is to use these metals as little as possible or
to completely replace them with metals that are cheaper and more accessible. One of such
metals that simultaneously exhibits relatively good electrocatalytic activity for the oxygen
evolution reaction is nickel.. In this master's work, several different catalysts, which were
synthesized at the National Insitute of Chemistry, are measured and analyzed. A gas
diffusion electrode (GDE) was used to study their activity, as it gives more realistic results
compared to a rotating disk electrode (RDE). RDE was used to study the activation of
catalysts, where it was found that the prior activation of β-Ni(OH)2 increases the activity
of the catalyst. For some samples the activity was increased by additional activation
where NiOOH is formed. Samples were also analyzed by scanning electron microscopy
and energy dispersive X-ray spectroscopy. A Tafel analysis was performed on the results
and the overvoltage η10; voltage when current density reaches 10 mA/cm2.
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