局部几何学,结构和电子共振增强来自CO的SFG信号在IR表面
Xia Li1, Stefania Baronio2, Susanne Gross1
1Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC, Vienna 1060, Austria.
概括
总频率生成 (SFG) 光谱显示,与光滑表面相比,在粗的表面上,CO吸附信号强度增加了八倍. 这种增强归因于局部表面等离子共振受到表面粗刺激.
科学领域:
- 表面科学是一门学科.
- 频谱学是一种光谱学.
- 材料科学 材料科学 材料科学
背景情况:
- 了解金属表面的吸附物行为对于催化和材料科学至关重要.
- 总频率生成 (SFG) 光谱是一种强大的振动光谱技术,用于研究表面.
- (Ir) 表面在各种催化应用中非常重要.
研究的目的:
- 用SFG光谱学研究表面粗度对Ir{111}上的CO吸附的影响.
- 阐明导致观察到的信号强度差异的潜在机制.
- 描述影响吸附剂与表面相互作用的表面特性.
主要方法:
- 总频率生成 (SFG) 光谱是主要的技术.
- 表面特征包括奥格尔电子光谱 (AES),低能离子散射 (LEIS),低能电子衍射 (LEED) 和扫描道显微镜 (STM).
- 在光滑和粗的表面上进行了比较研究.
主要成果:
- 对CO C-O拉伸模式的共振SFG信号强度的显著 (约为八倍) 增加在粗的Ir(111) 与光滑的Ir(111) 相比观察到.
- 表面表征证实了在修改的表面上存在喷雾诱导的局部粗 (粒).
- 考虑了各种因素,如覆盖范围,侧面相互作用,分子超极化,吸附几何,费米共振,吸附热振动带和表面等离子体.
结论:
- 在粗的Ir(111) 上增强的SFG信号主要归因于局部表面等离子体共振 (LSPR) 的激发,这种激发是由表面粗所促进的.
- LSPR增强了光引起的激发,导致观察到的信号放大.
- 表面形态在调节吸附分子的光谱信号方面发挥着至关重要的作用.
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