FTIR spectrum for the Fe3O4-Pd nanoparticles

These bands represent the characteristics of the functional groups and molecular vibrations of the sample. Characteristic Fe-O vibrations are expected in the region of 400-600 cm⁻¹ for Fe₃O₄ (magnetite).

The band at 580 cm⁻¹ corresponds to Fe-O stretching vibrations, which indicates Fe₃O₄. The remaining bands (644, 860, 1023 cm⁻¹) are attributed to other components or functional groups of the sample, possibly originating from surface modifications, contamination, or other materials mixed with Fe₃O₄ and Pd. The wide band near 3400 cm⁻¹ is sometimes assigned to O-H stretch vibrations of surface hydroxyls due to water adsorbed on the surface of the nanoparticle.