聚合物/金属复合物合成超导化合物的研究

Preparation of High-T_c Superconductor by Polymer-Metal complex Porcessing

使用聚合物/金属复合物(简称PMC)前体这一新型工艺,制备出单相态的超导化合物Y_1Ba_Cu_3O_x其工艺的累积时间比同类无机盐溶液法缩短60%,温度降低50℃～100℃,所得样品起始转变温度T_(c,始)=93.63K,零电阻温度T_(c零)=90.09K,转变宽度ΔT=0.5K。

Polymer-Metal Complex (PMC) processing is shown to be a new technique for the synthesis of high-Tc super conducting compounds. The product exhibits Tc at 90.09K and a narrow transition width. Tc (10%-90%), of 0.5K The magnetic susceptibility drops sharply at 95K. X-ray diffraction shows pure single phase of orthorhombic YBa CuO, the microstucture has been examined in detail bY scanning electron microscopy, which shows a single—crystal-like structure free from secondary plases and grain boundaries; Effects of preparative conditions and microstructures on the superconducting properties have been investigated. Based on the experimental results, we conclude that the polymer plays a significant role in PMC precursor. Microanalytical techniques were Used to detect the distribution of Y,Ba and Cu, Which identifies the sample to be highlyhomogeneous.The PMC processing is useful for various applications. The short time and low sintering temperature confirm the excellent sinterability of PMC precursor due its good homogeneity and monodispersed small particle size.