Robust PEEK-reinforced poly (aryl piperidinium) hydroxide exchange membrane for water electrolysis

Hydroxide exchange membrane water electrolysis (HEMWE) is garnering significant attention for large-scale green hydrogen production, owing to high operating current density and low capital cost. Hydroxide exchange membrane (HEM), a key component of the membrane electrode assembly (MEA), has been pursuing on improving its conductivity and dimensional stability for past several years. In this study, we develop a robust poly (ether-ether-ketone) (PEEK)-reinforced poly (aryl piperidinium) (TP-100) composite HEM (TP-100-PEEK) by a simple casting method. TP-100-PEEK shows excellent dimensional stability, good mechanical property and modest hydroxide conductivity. We also demonstrate a high-performance and durable HEMWE with the prepared TP-100-PEEK, achieving a high current density up to 3.5 A cm −2 at 2 V and over 1600 h long-term operation with a low decay rate of 51 μV h −1 at 1 A cm −2 . These results indicate that TP-100-PEEK has a significant potential for HEMWEs.