Cerium Oxide–Polysulfone Composite Separator for an Advanced Alkaline Electrolyzer

Jung Won Lee, ChangSoo Lee, Jae Hun Lee, Sang-Kyung Kim, Hyun-Seok Cho, MinJoong Kim, Won Chul Cho, Jong Hoon Joo, Chang-Hee Kim
2020 Polymers  
The intermittent and volatile nature of renewable energy sources threatens the stable operation of power grids, necessitating dynamically operated energy storage. Power-to-gas technology is a promising method for managing electricity variations on a large gigawatt (GW) scale. The electrolyzer is a key component that can convert excess electricity into hydrogen with high flexibility. Recently, organic/inorganic composite separators have been widely used as diaphragm membranes; however, they are
more » ... however, they are prone to increase ohmic resistance and gas crossover, which inhibit electrolyzer efficiency. Here, we show that the ceria nanoparticle and polysulfone composite separator exhibits a low area resistance of 0.16 Ω cm2 and a hydrogen permeability of 1.2 × 10–12 mol cm–1 s–1 bar–1 in 30 wt% potassium hydroxide (KOH) electrolyte, which outperformed the commercial separator, the Zirfon PERL separator. The cell using a 100 nm ceria nanoparticle/polysulfone separator and advanced catalysts has a remarkable capability of 1.84 V at 800 mA cm−2 at 30 wt% and 80 °C. The decrease in the average pore size of 77 nm and high wettability (contact angle 75°) contributed to the reduced ohmic resistance and low gas crossover. These results demonstrate that the use of ceria nanoparticle-based separators can achieve high performance compared to commercial zirconia-based separators.
doi:10.3390/polym12122821 pmid:33261186 fatcat:fh4grvgj5za77dnacas42wnnlq