In-situ Electrochemical Characterization of Ni and Amorphous Ni-based Nanoparticles in an Anion Exchange Membrane Water Electrolyser

Alkaline water electrolysis has regained interest as a promising technology for converting renewable energy into H2 due to the recent developments in anion exchange membranes. In this study, an anion exchange membrane water electrolyser (AEMWE) was fabricated to study the in-situ electrocatalytic performance of Ni-based materials. Ni is of particular interest due to its wide availability and intrinsic activity. Commercial Ni and amorphous (Ni, Co)-Nb-Y nanoparticles (NPs) were applied to AEMWE as electrocatalysts showing promising performance. Amorphous (Ni, Co)-Nb-Y NPs were produced through a novel two-step ball milling process. Fabrication methods (i.e. membrane electrode assembly (MEA) hot-pressing and optimized ionomer content) were critical for improving cell performance. AEMWE operating conditions (i.e. temperature and MEA compression) were investigated to enhance activity. The concentration of a supporting electrolyte dramatically increased the cell performance. Electrochemical testing showed that Ni displayed higher in-situ activity than the amorphous alloys. Cycled amorphous catalyst layers were more stable.