Physikalisch-Chemisches Institut, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 58, D-35392 Gießen, Germany.
Phys Chem Chem Phys. 2010 Nov 21;12(43):14596-608. doi: 10.1039/c0cp01018a. Epub 2010 Oct 12.
Multilayer samples of the type (YSZ|Sc2O3) × n with layer thicknesses between 8 nm (n=100) and 250 nm (n=5) were prepared on (0001) sapphire substrates by pulsed laser deposition (PLD). The samples were characterised using X-ray diffraction (XRD), scanning electron microscopy (HRSEM) and transmission electron microscopy (TEM/HRTEM, SAED (selected-area electron diffraction) and quantitative EELS (electron energy-loss spectroscopy)). The polycrystalline layers show a columnar microstructure, which is typical for the used preparation technique. The layers are highly textured and only one axial orientation relation is found between yttria-stabilised zirconia (YSZ), scandium oxide and the substrate: (0001) Al2O3‖(111) Sc2O3‖(111) YSZ. A preferred orientation relationship also exists for the azimuthal rotation of the crystallites, which was demonstrated by SAED, XRD pole figure measurements and fast Fourier transformation (FFT) of HRTEM micrographs. The interfaces between YSZ, Sc2O3 and the substrate are sharp and do not contain diffuse transition regions. Dislocations appear not to be arranged in regular arrays. With increasing interface density (thinner individual layers in the multilayer), the conductivity of the multilayers decreases. We relate this to the negative nominal misfit present at the YSZ|Sc2O3 interfaces (compressive stress in YSZ at the phase boundaries). This observation agrees well with the previously investigated case of YSZ|Y2O3 (A. Peters et al., Phys. Chem. Chem. Phys., 2008, 10, 4623), where tensile misfit strain was present in YSZ at the phase boundaries, leading to a conductivity increase.
采用脉冲激光沉积（PLD）技术在（0001）蓝宝石衬底上制备了（YSZ|Sc2O3）×n 型多层样品，其中 n 分别为 100（层厚 8nm）和 5（层厚 250nm）。利用 X 射线衍射（XRD）、高分辨率扫描电子显微镜（HRSEM）和透射电子显微镜（TEM/HRTEM、选区电子衍射（SAED）和定量电子能量损失谱（EELS））对样品进行了表征。多晶层呈现柱状微观结构，这是所采用的制备技术的典型特征。这些层具有高度的织构，在 YSZ、氧化钪和衬底之间仅发现一种轴向取向关系：（0001）Al2O3‖（111）Sc2O3‖（111）YSZ。通过 SAED、XRD 极图测量和 HRTEM 显微照片的快速傅里叶变换（FFT），也证明了在晶核的方位旋转方面存在优选的取向关系。YSZ、Sc2O3 和衬底之间的界面很锐利，没有弥散的过渡区。位错似乎没有规则排列。随着界面密度的增加（多层中较薄的单个层），多层的电导率降低。我们将这归因于 YSZ|Sc2O3 界面处存在的负名义失配（相界处 YSZ 中的压缩应力）。这一观察结果与之前研究的 YSZ|Y2O3 情况（相界处 YSZ 中的拉伸失配应变，导致电导率增加）一致。
