Our laboratory is working on developing next-generation separators for alkaline water electrolysis using a porous composite diaphragm composed of ceramic particles as a hydrophilic materials and a polymer matrix as a binder.

Our goal is to ensure that these separators exhibit both durability and ionic conductivity under the highly basic operating conditions (25-30% KOH) and temperatures (80°C) required for alkaline water electrolysis.

In order to achieve high performance in alkaline water electrolysis, it is important that porous membranes exhibit both uniform pore distribution and low pore size with high porosity to suppress gas crossover and maintain high ionic conductivity. Our research endeavors to decrease the incidence of micropores (>50 nm) and increase the prevalence of mesopores (2-50 nm) by improvement of various experimental procedures.

The key performance index of the separators include bubble point pressure (BPP), wettability, area resistance, and hydrogen permeability, which were measured ex-situ at room temperature. The results indicate that the developed membrane exhibits superior physical and electrochemical properties compared to the commercial Zirfon, confirming its potential as a high-performance alternative for separation in water electrolysis systems.

The developed porous membrane demonstrated excellent durability and performance, even in the harsh environment of alkaline water electrolysis. These results are expected to contribute significantly to the reduction of the cost of producing green hydrogen through water electrolysis.