fig2

Figure 2. (A) Illustration of the synthetic strategy of Fe-SAs/NPS-HC. (B) TEM and (C) AC HAADF-STEM images of Fe-SAs/NPS-HC. (D) Fe K-edge XANES and (E) Fe K-edge k₃-weighted Fourier transform (FT) spectra of Fe-SAs/NPS-HC, Fe₂O₃ and Fe foil. (F) ORR polarization curves, (G) J_k at 0.85 V and E_1/2 of Fe-SAs/NPS-HC, Fe-SAs/NPS-C and NPS-HC^[100]. TEM: Transmission electron microscopy; HAADF-STEM: high angle annular dark field scanning TEM; ORR: oxygen reduction reaction.