Magnetic and structural properties of Cu0.85Fe0.15O system synthesized by co-precipitation

Cu_0.94Fe_0.06O and Cu_0.85Fe_0.15O samples were synthesized by using the co-precipitation chemical method. Starting from aqueous solutions of copper nitrate, CuO (NO₃)₂ 3H₂O, iron nitrate, Fe (NO₃)₃ 9H₂O and sodium hydroxide as precipitating agent, NaOH. The precipitate of three samples for Cu_0.94Fe_0.06O and five for Cu_0.85Fe_0.15O of fine powder were calcined for 5 h at different temperatures. The obtained X rays diffraction patterns refined by the Rietveld method show the CuO characteristic pattern, showing that the Fe atoms enter to replace Cu atoms. Furthermore, it was obtained that the crystallite size decreases with calcination temperatures for Cu_0.94Fe_0.06O. The transmission Mössbauer spectroscopy showed that the samples present a disordered paramagnetic behavior due to the big value of the half-width of line of the quadrupolar splitting. Vibrating sample magnetometry confirms the paramagnetic character. The XRD results indicate that the material is nanostructured, due that the crystallite sizes are of the order of 10 nm for Cu_0.94Fe_0.06O and 40 nm for Cu_0.85Fe_0.15O.