fig6

Figure 6. PEM characterizations. (A) ⁵⁷Fe Mössbauer spectra of Fe/Zr-N-C; (B) Fe K-edge XANES spectra (C) and FT of Fe K-edge EXAFS spectra for Fe-N-C, Fe/Zr-N-C, reference Fe foil, and Fe₂O₃; Reprinted with permission from^[81]. (D) μ-computed tomography of MEA. Reprinted with permission from^[83]