有机分子的硫与氧的活性在Ge100) - 2 x 1表面
Jessica S Kachian1, Stacey F Bent
1Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|May 6, 2009
概括
含硫的有机分子比含氧的有机分子更强烈地与表面结合. 这种差异是由于硫.
科学领域:
- 表面科学是一门学科.
- 材料化学 材料化学
- 物理化学 物理化学
背景情况:
- 了解半导体表面的分子吸附对于设计新材料和新设备至关重要.
- 含有硫和氧的有机分子表现出不同的化学行为.
- (Ge) 是一个关键的半导体材料,在电子和催化中具有潜在的应用.
研究的目的:
- 研究和比较含硫和含氧有机分子的吸附机制和强度在Ge100) -2 x 1表面.
- 阐明原子 (硫与氧) 在分子吸附中的作用.
- 提供有关有机吸附剂和表面之间的化学结合的见解.
主要方法:
- 多重内部反射红外 (MIR-IR) 光谱法用于识别吸附物种和结合配置.
- 密度函数理论 (DFT) 计算以确定吸附能,反应路径和键强度.
- 变量温度研究来分析吸附-脱附动力学.
主要成果:
- 乙醇和乙乙醇通过素-H键解离吸附,而S-H解离比O-H更受青.
- 甲基乙和甲基硫化物通过异构原子的dative结合吸附,在更高的温度下可逆消化.
- 硫 - (S-Ge) 的原性键比氧 - (O-Ge) 的原性键总是更强,并且随着吸附基团的体积增加,键强度会增加.
结论:
- 与含氧的同类分子相比,含硫的有机分子在 Ge ((100) 上具有更强的吸附性.
- S-Ge 键的增强稳定性影响了吸附行为和表面化学.
- DFT计算准确地预测实验观测,为未来的表面化学研究提供了可靠的工具.
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