Substitution-driven structural, optical and magnetic transformation of Mn, Zn doped BiFeO3

Abstract Mn, Zn doped and pure BiFeO 3 were prepared by sol–gel method. The 5% and 10% Zn-doped phase crystallites have a rhombohedral symmetry ( R3c ) structure. Doped with 5% Mn, BiFeO 3 contains both rhombohedral ( R3c ) and tetragonal phase ( P4mm ) while 10% Mn gives a rise to tetragonal phase ( P4/mbm ). Raman and Fourier Transformed Infrared spectra also confirmed the structure transformation. Compared with pure BiFeO 3 , Mn-Zn doped samples present intense blue shift as shown in UV-Visible diffuse absorption together with the decreased direct optical band gap. The substitution of Mn ions for Fe enhances ferromagnetic properties while the Zn-doped ones show linear paramagnetism. Owing to the interactions between the ferromagnetic and antiferromagnetic microdomains, Mn and Zn co-doping results in a large remanent magnetization ( Mr ) of 0.045 emu/g.