Highly Active Binder Free Plasma Sprayed Non-Noble Metal Electrodes for Anion Exchange Membrane Electrolysis at Different Reduced KOH Concentrations

Abstract

Alkaline anion exchange membrane water electrolysis (AEMWE) is considered to be an alternative to proton exchange membrane water electrolysis (PEMWE) and conventional alkaline water electrolysis (AWE), owing to the use of non-precious metal and avoiding high alkaline concentration electrolyte, respectively. Here, we report a highly efficient AEMWE design using the fabrication of membrane-electrode assembly (MEA) by simply sandwiching anion exchange membrane between electrodes developed by plasma spraying of NiMoAl for cathode and NiAl for anode in various low concentrated KOH solutions (0.1 to 1.0M). The first impression from the electrochemical characterization is that a higher KOH concentration has positive effects on the overall cell performance. However, this effect is limited at higher KOH concentration. The cell operated in 1.0M KOH exhibits the highest current density of 0.44 A/cm² at 1.80 V, which is very close the one, 0.5 A/cm² at 1.80 V, in 6.0M KOH achieved in AWE.