Fig. 1.

Synthesis and characterization of layered K₃Fe₂[PcFe–O₈] MOF. a Schematic illustration for the synthesis of Fe₂[PcFe–O₈] framework with iron ions and organic PcFe-OH₈ linkers connected by coordination bonds (light cyan: C; blue: N; light pink: O; orange: Fe³⁺ in the phthalocyanine ring; green: Fe²⁺ in the linkage; H atoms and K⁺ counter-ions omitted for clarity). The interval between layers is about 3.3 Å along the c-axis; b Experimental PXRD pattern (organge curve) and that of calculated (DFT) AA-serrated stacking structures (dark cyan curve) of K₃Fe₂[PcFe–O₈]; c HRTEM image of K₃Fe₂[PcFe–O₈]. Scale bar: 5 nm. Inset: corresponding FFT analysis; d Normalized Fe K-edge XANES spectra of K₃Fe₂[PcFe–O₈], Fe foil, FeO, Fe₂O₃, and PcFe-OH₈. Insert: enlarged pre-edge region in Fe K-edge XANES spectra; e, Fourier transformation EXAFS spectra at Fe K-edge of Fe₂[PcFe–O₈] with Fe₂O₃ and PcFe-OH₈ as contrast