Chapter 7
Conclusion and outlook
7.1 Conclusion
The overall aim of this thesis has been to investigate and improve the performance
of an abundant catalytic material for oxygen evolution, MnOx. The work
was motivated by the important role of electrolyzers in the future energy infrastructure,
where intermittent renewable sources must be exploited to their full
potential. To do so, energy storage and carbon neutral fuels production are key
issues, which can be alleviated with electrolysis. Electrolyzers based on Polymer
Electrolyte Membrane cells are particularly promising but are acidic in nature
and therefore limits the catalysts choice to noble metal based materials. Thus,
a renewed research eort into identifying materials for oxygen evolution based
on abundant elements is highly relevant.
Finding and characterizing catalysts for electrolysis is not a new research eld
and a literature review was dedicated to bring the present thesis into the relevant
context. In the past decades a big emphasis has been put on understanding
the oxygen evolution reaction and on nding descriptors that could predict the
optimal material properties. In more recent years many new catalysts have
been reported for alkaline solutions, however, for acidic electrolytes very little
progress has been made for materials not based on noble metals. Furthermore,
rigorous stability tests were not often carried out. These shortcomings were
therefore addressed in this thesis.
In chapter 4 the aim was therefore to establish stability tests based on mass loss
analysis. From short term electrochemical characterization there are no guarantees
that a stable performance indicate material stability. Instead, it was shown