Study of N-bridged diiron phthalocyanine relevant to methane oxidation: Insight into oxidation and spin states from high resolution 1s core hole X-ray spectroscopy
| Autor: | Leonardo X. Alvarez, Pavel Afanasiev, Janine C. Swarbrick, Olga V. Safonova, Alexander B. Sorokin, Evgeny V. Kudrik, Pieter Glatzel |
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| Přispěvatelé: | BIOVERT (BIOVERT), Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), RAFFINAGE (RAFFINAGE) |
| Jazyk: | angličtina |
| Rok vydání: | 2012 |
| Předmět: |
X-ray spectroscopy
Spin states 010405 organic chemistry Process Chemistry and Technology [CHIM.CATA]Chemical Sciences/Catalysis 010402 general chemistry 7. Clean energy 01 natural sciences [SDE.ES]Environmental Sciences/Environmental and Society Catalysis XANES 0104 chemical sciences chemistry.chemical_compound Nuclear magnetic resonance Transition metal chemistry Catalytic cycle 13. Climate action Oxidation state Phthalocyanine Physical chemistry General Environmental Science |
| Zdroj: | Applied Catalysis B: Environmental Applied Catalysis B: Environmental, Elsevier, 2012, 113, pp.43-51. ⟨10.1016/j.apcatb.2011.11.028⟩ |
| ISSN: | 0926-3373 |
| DOI: | 10.1016/j.apcatb.2011.11.028⟩ |
| Popis: | BIOVERT:RAFFINAGE+EKU:ASO:PAF; mu-Nitrido diiron phthalocyanine [PcFe+3.5NFe+3.5Pc](0) is a highly efficient catalyst, able to oxidize methane under near-ambient conditions. In this work, high resolution X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS) were applied to study iron species in the series of mu-nitrido diiron phthalocyanines including initial [PcFe+3.5NFe+3.5Pc](0) and oxidized complexes [(PcFeNFePc)-N-IV-Pc-IV]+PF6 and [(PcFeNFeIV)-N-IV(Pc center dot+)]Br-2+(2) as model compounds for the intermediates in the catalytic cycle. These systems contain 3d(4) configuration of iron in high oxidation state Fe(IV). XES spectra of K beta line are sensible to the local iron spin density and show unexpected difference in the spin state between the initial [PcFe+3.5NFe+3.5Pc](0) (LS), one-electron oxidized [(PcFeNFePc)-N-IV-Pc-IV]+PF6 (HS) and two electron oxidized cation radical species [(PcFeNFeIV)-N-IV(Pc center dot+)]Br-2+(2) (LS). Fe K-edge XANES spectra were recorded at the fluorescence energy of the main K beta(1.3) line or K beta' line in the K beta emission spectrum. The conclusions of RIXS study corroborated XES data. Our study suggests that the main catalytic pathway of oxidation includes two-electron transformation from the LS initial complex to the LS two-electron oxidized [(PcFeNFeIV)-N-IV(Pc center dot+)(O)](0) to generate powerful oxidant able to oxidize methane via two-electron process. (C) 2011 Elsevier B.V. All rights reserved. |
| Databáze: | OpenAIRE |
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