Electrochemical study on the effect of hydrogen on the passive film of selective laser melted 316L stainless steel in a proton exchange membrane water electrolyzer environment

The effect of hydrogen on the passivation behavior and electrochemical characteristics of selective laser melted (SLMed) 316L stainless steel in a simulated anode environment for a proton exchange membrane water electrolyzer (PEMWE) was studied. The results indicate that hydrogen charged into the sample increased the ratio of superficial Fe²⁺/Fe³⁺ and OH⁻/O²⁻, increased the concentration of point defects, reduced the film thickness, and weakened its protective effect. The film near 0.6 V_SCE showed n-type semiconductor behavior. Hydrogen charging resulted in a higher defect density and thinner space charge layer in the film, which promoted the invasion of aggressive ions.