EXAFS and XANES investigations of CuFe2O4 nanoparticles and CuFe2O4-MO2 (M = sn, ce) nanocomposites

Structural investigations were performed on combustion synthesized CuFe2O4 nanoparticles and CuFe2O4-MO2 (M = Sn, Ce) nanocomposites in different compositions, by means of X-ray absorption fine structure spectroscopy. The studies on CuFe2O4 nanoparticles reveal that the samples have a structure analogous to that of the bulk material, wherein all the copper ions occupy the octahedral sites and the iron ions are distributed between the tetrahedral and octahedral sites. The XAFS investigations on CuFe2O4-SnO2 and CuFe2O4- CeO2 nanocomposites show that the incorporation of the tetravalent metal ions in the spinel lattice does not alter the local structure around copper and iron in CuFe2O4 nanoparticles. The X-ray diffraction pattern indicates CuFe2O4 as a single phase in the nanoparticles and shows the incorporation of metal ions in the spinel structure in addition to the existence of MO2 and CuFe2O4 Phases in CuFe2O4-MO2 nanocomposites. The nanometric size of the as-synthesized materials has been confirmed by transmission electron microscopy studies. The high-resolution transmission electron microscopy investigations also confirm that CuFe2O4 exists as a single phase and reveal the composite nature of CuFe2O4-MO2 materials.