Summary
Bipolar
membranes dissociate water (H2O-> H+ + OH-) at the interface between a
proton and a hydroxide conductor under applied bias. This is being exploited
industrially in electrodialysis to produce acid and base, and could be of great
value for water and CO2 electrolyzers.
Recently,
some of us introduced a new BPM assembly and characterization platform, based
on membrane electrode assemblies (MEAs), which are used for water electrolyzers
and fuel cells, and which continuously apply pressure over all BPM components
during operation. This way, we designed highly active BPMs with record-high
current densities. However, despite this progress, the performance is not yet
at levels needed for new applications. Conversely, we need to better understand
the BPM junction, not only for BPM electrolyzers and fuel cells, but also
electrodialysis.
For the latter,
self-supported, free-standing BPMs remain of key significance, as MEAs are too
bulky to be used in stacks comprising 50-100 in-series connected BPMs. However,
currently, the performance and structural differences between traditional,
freestanding BPMs and ones in the MEA are not known. To strengthen scientific
exchange and accelerate BPM R&D we need to understand these differences. In
APRiCOT, the German BPM experts at RWTH Aachen (RWTH) and the Fritz Haber
Institute (FHI) will leverage the world-expert knowledge in nanoassembly and
(2D) materials growth of the French CNRS Centre Interdiciplinaire de
Nanoscience de Marseille (CINaM) and the Institut Europeen des Membranes (IEM)
to obtain unprecedented control and understanding of the BPM junction. This in
turn might lead to high performing small-scale lab devices that motivate more
BPM R&D in the future.
