Self-adhesive ionomers for alkaline electrolysis: Optimized oxygen evolution electrode

The production of hydrogen by low-temperature water electrolysis using anion conductive membranes combines the favorable attributes of alkaline electrolysis and proton exchange membrane electrolysis. The anion conductive ionomer in the oxygen-producing anode is a critical part of the three-dimensional electrode. The ionomer in the anode facilitates hydroxide and water conduction to the anode catalyst particles from the liquid alkaline electrolyte flow channel, and binds the catalyst to the porous transport layer. 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, thereby providing sufficient water transport. 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. Optimization of the catalyst and self-adhesive ionomer content within the anode led to mechanically durable and energy-efficient water electrolysis.

Automated summary

The production of hydrogen by low-temperature water electrolysis using anion conductive membranes combines alkaline electrolysis and proton exchange membrane electrolysis. The use of self-adhesive anode ionomers improves anodic polarization and cell durability. Optimizing the catalyst and self-adhesive ionomer content within the anode leads to mechanically durable and energy-efficient water electrolysis.