A Raman study on Zinc-substituted Cobalt ferrites, with different Zn(II) contents in each sample of formula: CoFe₂O₄ (), ZnCoFeO₄ (), ZnCoFeO₄ (), ZnCoFeO₄ () is reported. These samples show the same crystallite size (∼6 nm), particle size (∼7 nm) and particle size distribution (∼20%) and they have been synthesized through heating up surfactant-assisted thermal decomposition of metalorganic precursors. The effect of Zn(II) substitution in the cationic distribution is investigated by using the known metal-oxygen vibrational modes in tetrahedral and octahedral sites. The presence of Zn(II) metal ion is determined through the band at 150 cm (T(1) phonon mode), which is not present in the pure Co-ferrite, a blue-shift of the vibrational mode depending on Zn(II)/Co(II) cationic distribution and a shoulder at ∼250 cm, which appears when zinc enters in the structure, and a broadening and a red-shift in the phonon mode is observed in Raman spectra of samples. Interestingly the latter represents a potential key probe to monitor the Zn(II) presence in Zn-substituted Co-ferrites.
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