Synthesis, magnetic and electrical transport properties of magnetoresistance material Sr₂FeMoO₆ by microwave sintering

详细信息	查看全文 | 推荐本文 |

• 作者：Yongqing Zhai ; ^{zhaiyongqinghbu@163.com} ; Jing Qiao ; Guoyan Huo ; Shaoqiang Han
• 关键词：Microwave synthesis ; Sr2FeMoO6 ; Magnetic and electrical transport properties ; Magnetoresistance
• 刊名：Journal of Magnetism and Magnetic Materials
• 出版年：2012
• 期刊代码：31_03048853
• 类别：ph
• 出版时间：July, 2012
• 卷：324
• 期：13
• 页码：2006-2010
• 文件大小：410 K

摘要

Magnetoresistance material Sr₂FeMoO₆ with double perovskite structure was synthesized by microwave sintering method using SrCO₃, Fe₂O₃ and MoO₃ as raw materials, with MnO₂ for microwave absorber. The phase structure, magnetic and electrical transport properties were investigated by X-ray powder diffraction (XRD) and vibrating-sample magnetometer. XRD analysis shows that the as-synthesized sample is Sr₂FeMoO₆ with tetragonal crystal structure and I4/mmm space group. The unit cell parameters are a=0.5587 nm, c=0.7894 nm, volume=0.2464 nm³. The calculated grain size of the sample is 31.62 nm, which is obtained by the Scherrer formula using the diffraction data. Magnetism testing results show that the sample Sr₂FeMoO₆ is ferromagnetic with the magnetic transition temperature of about 380 K. Under 1.0 T magnetic field, the saturation and spontaneous magnetization of Sr₂FeMoO₆ is 1.25 渭_B/f.u. and 1.00 渭_B/f.u. at room temperature. The magnetoresistance ratio of the sample is 28%. Electrical transport properties testing results indicate that the sample exhibits typical semiconductor behavior. The conductive mechanism of Sr₂FeMoO₆ is highly dependent on temperature: within the temperature range of 100-300 K, the mechanism is attributed to the small polaron variable-range hopping model; while it is ascribed to the adiabatic small polaron model within the temperature range of 80-100 K.