In situ iron K-edge X-ray absorption near edge structure, XANES, has been employed to examine the axial coordination of (µ-OXO)bis [iron meso-tetrakis(4-methoxyphenyl)porphyrin] (FeTMPP) 2 O, irreversibly adsorbed on a high area carbon substrate, Black Pearl (BP), as a function of applied potential. Analysis of the XANES provides conclusive evidence that the coordination about Fe 3+ in the supported, fully oxidized macrocycle is remarkably different from that about Fe 2+ in the corresponding fully reduced macrocycle. In the adsorbed, oxidized state, (FeTMPP) 2 O retains its µ-OXO character and it undergoes a two-electron reduction to yield predominantly four-coordinate square-planar FeTMPP without axial ligation.
ASJC Scopus subject areas
- Colloid and Surface Chemistry