Advanced Surface Engineering of Porous Transport Electrodes to Improve Membrane–Electrode Interfaces and Surface Areas for Anion Exchange Membrane Water Electrolyzers

The development of efficient anion exchange membrane water electrolyzers (AEMWEs) necessitates innovative approaches to enhance the interfacial compatibility between the porous transport layer (PTL) and the anion exchange membrane (AEM). In this study, a simple two-step method was employed to modify the PTL surface with a Ni nanoparticle layer, yielding a multifunctional porous transport electrode (PTE), termed FeNN-NiFr. The Ni nanoparticle layer on the PTL surface improved the PTE–AEM interface by increasing the interfacial contact area with the AEM and the electrochemical surface area of the PTE. Electrochemical characterization confirmed that the Ni nanoparticle modification reduced the ohmic and reaction resistances and maintained the porosity and mass transport ability of the PTL, resulting in improved performance across low- and high current density regions. The optimal Ni nanoparticle loading of 6 mgNi cm–2 on FeNN-NiFr achieved a current density of 1.0 A cm–2 at a lower operating voltage of 1.71 V in a single-cell AEMWE, which is a 0.24 V improvement over unmodified electrodes. This study highlights the potential of Ni nanoparticle-modified PTEs in advancing AEMWE technology by addressing interfacial challenges and achieving significant performance gains.