本研究以電紡絲製程製備TiO2及ZnO電紡絲一維奈米結構，將其添加於Y-Ba-Cu-O (YBCO)超導塊材中，並且與未添加的樣品和添加奈米粒子的樣品比較其對超導性質及微結構的影響。
以電紡絲製程製作TiO2及ZnO一維奈米柱狀結構（NRs），TiO2 NRs的平均直徑為288.2nm；而ZnO NRs以兩種不同濃度的前驅物溶液製備，其直徑分別為51.5nm和198.6nm。實驗結果發現，少量添加（0.01~0.1wt%）NRs於YBCO塊材不會影響其單晶粒的成長。
分別添加TiO2電紡絲和ZnO電紡絲的樣品，其最大擄獲磁場強度（Trapped field，Bt）都可以提升到0.13T為大於標準未添加塊材（0.08T）和添加奈米粒子的樣品（0.09T）。在臨界電流密度（Critical current density，Jc）方面，添加TiO2 NRs和ZnO NRs的樣品在在77K零場下的Jc值分別為5.2x104/cm2和4.8x104/cm2，約為未添加樣品（2.5x104/cm2）的兩倍，同時皆高於添加TiO2奈米粒子（3.3 x104/cm2）和ZnO奈米粒子（3.2 x104/cm2）的樣品。此外，本研究同時添加CeO2於上述添加NRs的樣品中，發現其超導性質，如Bt和Jc皆有效地被提升。
觀察添加電紡絲塊材的微結構發現，添加NRs不會影響塊材中的非超導第二相Y2BaCuO5 (Y211)的尺寸及分布；值得令人注意的是，在添加TiO2 NRs和ZnO NRs超導塊材的基地相中發現形貌及直徑與一開始添加的NRs相似的柱狀結構，顯示電紡絲在高溫熔融製程後仍能保持其柱狀結構並分布於塊材中，增加了第二相與超導相之間的界面面積，因此提供更多位置的釘扎，使YBCO超導性質提升。另一方面，添加NRs樣品的超導性質高於添加奈米粒子的樣品，主要是因為一維柱狀結構在超導體中有較好的釘扎能力。

This study presents the enhanced superconducting properties of single grain Y-Ba-Cu-O (YBCO) bulk superconductors by the addition of TiO2 and ZnO 1D nano-structures by electrospinning method and compares with that for the undoped sample and samples with the addition of nanoparticles (NPs).
The TiO2 and ZnO nanorods (NRs) were fabricated by electrospinning method to be effective pinning centers of columnar defects in bulk YBCO superconductors. The mean diameter of TiO2 NRs was 288.2nm. There were two different sizes of ZnO NRs with mean diameter of 51.6nm and 198.6nm respectively, prepared from different concentration of precursor solutions. From the results, the YBCO bulks with the addition of NRs (0.01 ~ 0.1wt%) grew a single grain without sub-grains appearing.
The maximal values of Bt of YBCO bulks doped with TiO2 and ZnO NRs are 0.13T and 0.12T, respectively, which was higher than that of the undoped sample (0.08T) and samples with the addition of TiO2 and ZnO nanoparticles (0.09T). The Jc at 77K and self field of YBCO bulks with the addition of TiO2 and ZnO NRs were enhanced to 5.2x104/cm2 and 4.8x104/cm2 respectively, which were twice as high as that of the undoped sample (2.5x104/cm2), and higher than that of the samples with the addition of TiO2 NPs (3.3 x104/cm2) and ZnO NPs. (3.2 x104/cm2). In addition, CeO2 were also added in the samples with the addition of NRs. The enhanced superconducting properties such as Bt and Jc were found.
Microstructure analysis indicated that Y211 phase were similar with those in the undoped sample, including the size and distribution. It is noticeable that columnar structure of NRs with similar size and shape as the precursor NRs were found in the matrix of TiO2 and ZnO NRs doped YBCO bulks, showing that there was no reaction occurring between NRs and YBCO bulks during the melting process. Consequently, the enhanced superconducting properties were contributed to the increased interface areas between the NRs and matrix. For the samples doped with NRs and NPs, the NRs samples showed higher pinning efficiency and resulted in the enhancement of superconducting properties of YBCO bulks.

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