Toward Simplified Electrode Design: Development of Nickel-Efficient Catalytic NanoPTL for Sustainable AEM Water Electrolysis

Nickel-based porous transport layers (PTLs) are widely used in anion exchange membrane water electrolysis (AEMWE) owing to their chemical stability in alkaline media, electrical conductivity, and efficient transport of gases and electrolyte. However, the rising cost and supply concerns of nickel necessitate more material-efficient solutions. This study introduces a freestanding, bifunctional catalytic Ni nanoPTL for AEMWE, synthesized via magnetically assisted chemical reduction. By tuning the nanowire morphology through seed concentration, the nanoPTL achieves up to 90% nickel reduction while enhancing the surface area and mechanical robustness. Electrochemical and structural analyses reveal strong morphology–activity correlations, with the nanoPTL outperforming commercial benchmarks in the hydrogen evolution reaction (HER) and showing promising oxygen evolution reaction (OER) performance. Single-cell tests confirm the stability and integration potential of the nanoPTL, underscoring both its potential and areas for improvement toward cost-effective, sustainable, and high performance AEMWE electrode design.