X‐ray diffraction analysis of powder and thin film of (Gd1‐x Yx)2O3 prepared by sol‐gel process
X‐ray diffraction analysis of powder and thin film of (Gd1‐x Yx)2O3 prepared by sol‐gel process
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溶胶-凝胶法制备的(Gd1-x Yx)2O3粉末和薄膜的X射线衍射分析
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
L. Arda
中科院分区：
文献类型：
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作者：
Z. Heiba;L. Arda
采用溶胶-凝胶法制备了混合氧化物（Gd1‐xYx）2O3（0.0≤x≤1.0）粉体和薄膜。收集X射线衍射数据，采用Rietveld细化法进行晶体结构和微观结构分析。所有样品都具有相同的晶体体系，并在整个x范围内形成固溶体。在空间群Ia3的两个非等效位置8b和24d上，阳离子Gd3+和Y3+的分布对于(x)的所有值都是随机的。发现晶格参数随组成(x)线性变化。相互替换Gd3+和Y3+会导致阳离子位置x坐标的系统性降低（24d）和氧坐标的轻微变化。沿不同晶体学方向进行晶体尺寸和微应变分析，发现各向异性变化与组成参数(x)有关。平均晶粒尺寸为75 ~ 149 nm，均方根值为0.027 ~ 0.068 × 10‐2。采用溶胶-凝胶浸涂工艺，成功地在立方体织构Ni（001）带衬底上生长出具有高度面外和面内取向的gd1.841 y0.1590 o3（400）缓冲层。所得缓冲层无裂纹、无针孔、致密、光滑。YbBa2Cu3O7‐x （YbBCO）薄膜可以用溶胶-凝胶浸渍技术在得到的缓冲层上（00l）外延生长。（©2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim）
The mixed oxide (Gd1‐xYx)2O3 (0.0 ≤ x ≤ 1.0) were synthesized, as powder and thin film, by a sol‐gel process. X‐ray diffraction data were collected and crystal structure and microstructure analysis were performed using Rietveld refinement method. All samples were found to have the same crystal system and formed solid solutions over the whole range of x. The cationic distribution, Gd3+ and Y3+, over the two non‐equivalent sites 8b and 24d of the space group Ia3 is found to be random for all values of (x). The lattice parameter is found to vary linearly with the composition (x). Replacing Gd3+ and Y3+ by each other introduces a systemic decrease in the x‐coordinate of cation position (24d) and slight changes in the oxygen coordinates. Crystallite size and microstrain analysis is performed along different crystallographic directions and anisotropic changes are found with the composition parameter (x). The average crystallite size ranges from 75 to 149 nm and the r.m.s strain from 0.027 to 0.068 x10‐2. Textured Gd1.841Y0.159O3 (400) buffer layers, with a high degree of alignment in both out‐plane and in‐plan, are successfully grown on cube textured Ni (001) tape substrates by sol–gel dip coating process. The resulting buffer layers are crack‐free, pinhole‐free, dense and smooth. YbBa2Cu3O7‐x (YbBCO) thin film could be (00l) epitaxially grown on the obtained buffer layer using sol–gel dipping technique. (© 2007 WILEY ‐VCH Verlag GmbH & Co. KGaA, Weinheim)