Structural features of CeO2(111) revealed by dynamic SFM
Structural features of CeO2(111) revealed by dynamic SFM
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DOI：
10.1088/0957-4484/16/3/008
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发表时间：
2005-01
期刊：
影响因子：
3.5
通讯作者：
S. Gritschneder;Y. Namai;Y. Iwasawa;M. Reichling
中科院分区：
文献类型：
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作者：
S. Gritschneder;Y. Namai;Y. Iwasawa;M. Reichling
二氧化铈是一种绝缘材料，在各种催化领域都很重要，通常用作氧气储存器。CeO 2的（111）表面具有催化活性，我们通过动态力显微镜研究了该表面的各种氧化态，这种分析最终可能有助于建立催化的结构-功能关系。我们提出了高分辨率的图像和CeO 2（111）的表面特征的原子细节，如梯田结构，台阶边缘，扭结和六角形坑，自然形成的表面制备过程中溅射和退火周期。我们发现，这样的结构可以很好地成像与原子分辨率，他们表现出的形态特征，是显着不同的细节从那些劈开的CaF 2（111），表面具有完全相同的晶体结构和非常相似的晶格常数和离子半径。在这项研究中，我们不断监测尖端顶点的形状，并证明高质量的原子分辨率成像是可能的一个尖端，虽然尖端顶点是急剧变化的磨损在45小时的扫描。
Cerium dioxide is an insulating material that is important in various fields of catalysis and often used as an oxygen reservoir. The (111) surface of CeO2 is catalytically active and we study this surface in its various oxidation states by dynamic force microscopy, an analysis that may eventually help to establish structure–function relationships for catalysis. We present highly resolved images and atomic details of surface features on CeO2(111) like terrace structures, step edges, kinks and hexagonally shaped pits that are naturally formed during surface preparation by sputtering and annealing cycles. We find that such structures can be well imaged with atomic resolution and that they exhibit morphological characteristics that are significantly different in details from those of cleaved CaF2(111), a surface with exactly the same crystallographic structure and very similar lattice constants and ionic radii. In this study, we continuously monitor the shape of the tip apex and demonstrate that high quality atomic resolution imaging is possible with one tip, although the tip apex is drastically changed by wear during 45 h of scanning.