Durability and Performance of Poly(norbornene) Membranes and Ionomers in Alkaline Electrolyzers

Abstract

The anion conductive ionomer in the oxygen-producing anode is a critical part of the three-dimensional electrode in the anion exchange membrane alkaline electrolysis. In this study, self-adhesive anode ionomers were designed to chemical bond the anode catalyst particles to the porous transport layer and to the ionomer. It was found that high ion exchange capacity ionomers were not needed for effective electrode polarization because the anode was fed with alkaline electrolyte through the flow channel. The hydrophobic nature of anode ionomer and intimate contact with the catalyst by chemical bonding to the catalyst was key to improving anodic polarization and cell durability. The catalyst and self-adhesive ionomer contents of anode were optimized for the mechanically durable and energy-efficient alkaline water electrolysis.