Fig. 2: Visualizing water-induced Mg passivation and its inhibition by the PDG interphase.

a Optical image of large-size of PDG-Mg foil. b XRD patterns and (c) Raman spectrum of pristine Mg and PDG-Mg electrode. d High-resolution C 1 s XPS spectrum of PDG-Mg electrode. Photographs showing water wetting behavior on (e) pristine Mg and (f) PDG-Mg electrodes during the water treatment.