Cu doping effect of hematite (α-Fe2−xCuxO3): Effect on the structural and magnetic properties

We report Cu doped α-Fe2−xCuxO3 hematite [(x=0.0, 0.20 and 1.00)] structural and field-dependent magnetic properties with corundum structure shaped α-Fe2O3 samples are synthesized. We observed that the Raman spectra at higher doping concentration of Cu for x=1.00; A1g, Eg(1), Eg(4), and Eg(5) modes are disappeared. The Eu mode frequency increased and pronounced systematically as a function of Cu doping and it reaches a value of 703 cm−1 for (x=1.00). The magnetic field dependent properties of corundum structure shaped α-Fe2O3 as a function of Cu doping the obtained value of coercivity (Hc) and remanence (Mr) are increases systematically, which suggest that Cu doping at Fe site in α-Fe2O3 attributed to its enhanced shape and magneto-crystalline anisotropy. The oxidation state of Fe was analyzed in terms of Mössbauer spectroscopy and observed isomer shift δ values from room temperature Mössbauer data clearly shows oxidation sate of iron (Fe) is Fe+3 (ferric) and copper (Cu) is Cu2+ ions.