在Ru{0001}和Pt{111}上的第一层冰的生长和结构
Sabine Maier1,2, Barbara A J Lechner1, Gabor A Somorjai1,3
1Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|February 5, 2016
概括
对金属表面的水的研究显示,最初的水层
科学领域:
- 表面科学
- 凝聚物质物理
- 物理化学
背景情况:
- 在金属表面上吸附水对于理解各种现象至关重要.
- 最初的水层决定了随后的冰形成的结构.
- Ru(0001) 和 Pt(111) 是研究表面相互作用的模型系统.
研究的目的:
- 阐明Ru (0001) 和Pt (111) 上初始水层的分子层结构和生长.
- 研究从无形到晶体冰结构的转变.
- 找出影响冰形成的结构缺陷.
主要方法:
- 使用扫描道显微镜 (STM) 来实现分子级别的分辨率.
- 实验是在Ru (0001) 和Pt (111) 的金属表面进行的.
- 用不同的温度来观察不同的冰阶段.
主要成果:
- 第一个水层形成六角结构,与基质有序和无序.
- 这些六边形通过五边形和七边形单位连接,导致140K以下的更高层的无形冰生长.
- 在过渡到晶体冰时,初始层重新配置以匹配基板的六角对称性.
- 包括五个和八个环在内的结构缺陷被确定为域边界和堆叠缺陷.
- 这些缺陷有助于形成稳定的立方体冰.
结论:
- 第一个水层的结构极大地影响了冰的后续生长和阶段.
- 由于特定的界面安排和缺陷,形成了不稳定的无形和立方冰结构.
- 了解这些水界结构是控制冰形成过程的关键.
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