Soft-Templating Strategies for AEM Water Electrolysis: Catalyst Development and Substrate Optimization

In the pathway for a more sustainable world, hydrogen has been chosen as green energy vector, where anion exchange membrane water electrolysis (AEMWE) offers a cost-efficient alternative to proton exchange membrane electrolysis (PEMWE) by leveraging earth-abundant materials. Thus, in this work, a unique synthetic protocol, based on the molten salt-assisted self-assembly (MASA) method, is presented to produce both AEM anode and cathode based on NiFe and NiS, respectively. The method was employed for preparing binder-free catalyst-coated substrate (CCS) by dip-coating onto C-based porous transport layers (PTLs) and Ni fiber paper. In addition to the role of the substrates, the Ni:S and Ni:Fe ratios were also analyzed. In all the cases, electrodes were electrochemically characterized at three-electrode and single-cell level. The improvements in terms of synthesis simplicity and scalability provide a pathway to the rational development of high-performance and economically viable AEMWE systems at (semi)industrial level.