Coating development for potential application in PEM water electrolysis

Polymer electrolyte membrane water electrolysis (PEMWE) is an electrolysis technology for hydrogen production. The bipolar plate (BPP) and the porous transport layer (PTL) made of titanium are two costly components in the electrolyzers of PEMWE. Research has already evaluated the use of vacuum plasma spraying (VPS) for the fabrication of BPP and PTL. In this publication, the fabrication of PTL using atmospheric plasma spraying (APS) is investigated. By eliminating the need for vacuum technology, process costs could be reduced. In the paper, two titanium powders are processed with the three-cathode plasma spraying. First, the spraying parameters are developed in terms of coating porosity and oxidation of titanium with steel substrate. Based on this, thin titanium exponded metals are coated as PTL. The coating structure and the phase composition of the coatings are investigated by scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD).