XAS Investigation of Iron Substitution in Triclinic FeAPO34

I. Aron, A. Risti, N. Novak Tuar, A. Kodre, V. Kaui
2005 Physica Scripta  
Iron-modified aluminophosphate with a triclinic form of the chabazite topology FeAPO-34, synthesized hydrothermally from a fluoride medium, is analyzed by Fe K-edge XANES and EXAFS. XANES analysis reveals that the as-synthesized sample contains approximately equal amounts of Fe(II) and Fe(III) cations, while the oxidation state of iron in the template-free sample is Fe(III). EXAFS analysis confirms the incorporation of iron into different framework sites of the assynthesized FeAPO-34 with
more » ... FeAPO-34 with triclinic symmetry. In the template-free FeAPO-34 with rhombohedral symmetry, iron cations are located on tetrahedral sites, forming catalytically active acid and redox centers.
doi:10.1238/physica.topical.115a00753 fatcat:37wdvqcjnrc3nbcbctwd52qd4m