INVESTIGADORES
CADUS Luis Eduardo
artículos
Título:
DETERMINATION OF Fe4+ IONS IN PARTIALLY SUBSTITUTED PEROVSKITES La1-xCaxFeO3
Autor/es:
BARBERO BIBIANA P; CADUS LUIS E.; MARCHETTI GUSTAVO
Revista:
HYPERFINE INTERACTIONS
Editorial:
Springuer
Referencias:
Año: 2009 vol. 194 p. 367 - 379
ISSN:
0304-3843
Resumen:
The partial substitution for lanthanum in LaFeO3 perovskite with calcium,
a cation with lower oxidation state, causes an electronic unbalance. The X-ray
diffraction (XRD) and temperature-programmed reduction (TPR) results suggest
that, consequently, the elevation of the iron oxidation state to Fe(IV) occurs.
The Mössbauer spectroscopy studies confirm the onset of Fe(IV) to maintain the
structure electroneutrality. The quantification of Fe(IV) species is in good agreement
with the estimated amount from the hydrogen consumption in the TPR studies. This
shows that TPRa very simple technique widely used to characterize heterogeneous
catalystsis an appropriate technique to quantify Fe(IV) species in LaFeO3 substituted
perovskites. To verify the correct assignment of step corresponding to the
Fe(IV) reduction, the different iron species after each reduction step, during the TPR
experiment, were confirmed by Mössbauer spectroscopy in controlled atmosphere.3 perovskite with calcium,
a cation with lower oxidation state, causes an electronic unbalance. The X-ray
diffraction (XRD) and temperature-programmed reduction (TPR) results suggest
that, consequently, the elevation of the iron oxidation state to Fe(IV) occurs.
The Mössbauer spectroscopy studies confirm the onset of Fe(IV) to maintain the
structure electroneutrality. The quantification of Fe(IV) species is in good agreement
with the estimated amount from the hydrogen consumption in the TPR studies. This
shows that TPRa very simple technique widely used to characterize heterogeneous
catalystsis an appropriate technique to quantify Fe(IV) species in LaFeO3 substituted
perovskites. To verify the correct assignment of step corresponding to the
Fe(IV) reduction, the different iron species after each reduction step, during the TPR
experiment, were confirmed by Mössbauer spectroscopy in controlled atmosphere.3 substituted
perovskites. To verify the correct assignment of step corresponding to the
Fe(IV) reduction, the different iron species after each reduction step, during the TPR
experiment, were confirmed by Mössbauer spectroscopy in controlled atmosphere.