During the first year of the project, significant advances have been made to develop own components for an AEM electrolyzer that can operate at alkaline conditions. Some components have also been tested and shown promising results under saline conditions, and more challenging electrolytes (close to neutral pH and saline water) will be the focus of the next period of the project.
In particular, OER and HER electrocatalysts made of non-CRM or non-PGM (more relevant term from now on) have been synthesised and initial physico-chemical and electrochemical characterisations have been made. Some of the catalyst show very promising activity at the targeted electrolytes, and some of the electrocatalysts have also been tested in single-cell electrolysers under alkaline conditions, achieving excellent stability over long-term experiments.
Head groups for the anion exchange polymers have been prepared, showing very good stability and suitable ionic conductivity. In parallel, reinforced membranes have been synthesised and characterised, achieving the targeted mechanical strength. With the addition of suitable radical scavengers to improve chemical resistance, some suitable membranes have been prepared and will be shared to other ANEMEL partners to incorporate into single-cell and stack devices.
In the second reporting period, efforts have been focused on the further development of non-PGM OER and HER electrocatalysts capable to operate under the challenging electrolyte conditions mentioned in the project. The most promising catalysts have been deposited on electrode surfaces and tested in single-cell water electrolysers, achieving the target milestone of 1 A cm-2 at 2 V within the pH range 7-12.
The work on polymers and head groups have continued with the development of components with excellent stability under mild alkaline conditions. Preliminary tests show even better stability in saline conditions as expected since the oxidative degradation is less pronounced.
Finally, the work on the electrolyser stack has continued with the development and testing of the test station, and validation of a new patented flow pattern using commercially available components.