Jin Zhenlan, Park Changin, Song Kyu Jeong, Kang Sukil, Ko Kyeong-Eun, Park Chan, Ko Rock Kil, Han S W
J Nanosci Nanotechnol. 2015 Jan;15(1):642-6. doi: 10.1166/jnn.2015.8326.
We examined the local structural and the interfacial properties of YBa2Cu3O(7-x) (YBCO)/ZnO nanorods on SrTiO3 (STO) substrates using various measurements. Vertically aligned ZnO nanorods were synthesized on STO substrates using a catalyst-free metal-organic chemical vapor deposition. YBCO films were deposited ex-situ on the ZnO nanorods/STO templates using a DC magnetron sputtering deposition. X-ray diffraction revealed that the YBCO films were crystallized along their c-axes on the ZnO nanorods/STO templates. Transmission electron microscopy measurements demonstrated that YBCO filled the space between ZnO nanorods and that both interfaces of YBCO/ZnO nanorods and ZnO nanorods/STO were quite clean with no disorder. Polarization-dependent extended X-ray absorption fine structure measurements at the Cu K edge showed extra disorder in the CuO2 planes of YBCO/ZnO nanorods/STO, compared with that of YBCO/STO. The superconductivity transition temperature (T(c)) of YBCO/ZnO nanorods/STO was approximately 50 K whereas that of YBCO/STO was 93 K. The decrease of T(c) of YBCO/ZnO nanorods/STO was ascribed to the structural disorder of CuO2 planes as well as grain boundaries in the YBCO films.
我们使用各种测量方法研究了YBa2Cu3O(7-x)（YBCO）/ZnO纳米棒在SrTiO3（STO）衬底上的局部结构和界面性质。采用无催化剂的金属有机化学气相沉积法在STO衬底上合成了垂直排列的ZnO纳米棒。使用直流磁控溅射沉积法将YBCO薄膜非原位沉积在ZnO纳米棒/STO模板上。X射线衍射表明，YBCO薄膜在ZnO纳米棒/STO模板上沿其c轴结晶。透射电子显微镜测量表明，YBCO填充了ZnO纳米棒之间的空间，并且YBCO/ZnO纳米棒和ZnO纳米棒/STO的两个界面都非常干净，没有无序现象。在Cu K边进行的偏振相关扩展X射线吸收精细结构测量表明，与YBCO/STO相比，YBCO/ZnO纳米棒/STO的CuO2平面存在额外的无序现象。YBCO/ZnO纳米棒/STO的超导转变温度（T(c)）约为50 K，而YBCO/STO的超导转变温度为93 K。YBCO/ZnO纳米棒/STO的T(c)降低归因于CuO2平面的结构无序以及YBCO薄膜中的晶界。
