| Abstract: Nanosize lanthanide doped manganese zinc ferrites were prepared by hydrothermal precipitation route using Fe2(SO4)3, ZnSO4·7H2O, MnSO4·H2O and Ln(NO3)3(Ln=La, Ce, Nd) as raw materials, and characterized by XRD,TEM and VSM. The results of XRD and TEM showed that lanthanide doping amount should not exceed 0.1 to maintain Mn-Zn ferrites’ regular cubic spinel crystal structure and their good magnetic properties. The particles for Mn-Zn ferrites doped with different lanthanide elements were all uniformly sized nanoparticles with little aggregation and their sizes decreased in the order of La3+, Ce3+ and Nd3+. The VSM studies indicated that saturation magnetization (Bs) of lanthanide doped Mn-Zn ferrite was obviously greater than that of pure Mn-Zn ferrite, and its values increased in the order of La3+, Ce3+ and Nd3+, which is consistent with their 4f electrons’ numbers (4f0, 4f1 and 4f3, respectively). The changing trends with lanthanide content (x) of saturation magnetization (Bs) and coercitivity (Hs) of La3+, Ce3+ and Nd3+ doped Mn-Zn ferrites were different when x was less than 0.1, which might be due to the influences of the substitution of Fe3+ on the magnetic superexchange interactions between octahedral B sites and tetrahedral A sites. On the other hand, when x was larger than 0.1, their changing trends were similar to each other. |
