fig4

Figure 4. Structural characterization of the Ir/POP-Phen. (A) HR-TEM images of the Ir/POP-Phen; (B-E) EDX elemental mapping of the Ir/POP-Phen; (F) Abreaction-corrected HAADF-STEM image of the Ir/POP-Phen; (G) In-situ CO absorbed FT-IR spectra of the Ir/POP-Phen; (H) XANES spectra of Ir K-edge; (I) EXAFS Fourier transformed spectra. Ir/POP-Phen: Porous phenanthroline-based polymer-supported single-iridium-atom catalyst; HR-TEM: high-resolution-transmission electron microscopy; EDX: energy-dispersive X-ray; HAADF-STEM: high-angle-annular-dark-field scanning transmission electron microscopy; FT-IR: Fourier-transform infrared; XANES: X-ray absorption near-edge structure; EXAFS: extended X-ray absorption fine structure.