Ishizaki Takahiro, Saito Nagahiro, SunHyung Lee, Ishida Kaoru, Takai Osamu
EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan.
Langmuir. 2006 Nov 21;22(24):9962-6. doi: 10.1021/la052342u.
Alkyl organic monolayers with different alkyl molecular chain lengths directly attached to silicon were prepared at 160 degrees C from 1-decene (C10), 1-dodecene (C12), 1-tetradecene (C14), 1-hexadecene (C16), and 1-octadecene (C18). These monolayers were characterized on the basis of water contact angle measurement, ellipsometry, X-ray reflectivity (XR), X-ray photoelectron spectroscopy (XPS), and grazing incidence X-ray diffraction (GIXD) to elucidate the effect of the molecular chain length on the molecular arrangement and packing density of the monolayers. Water contact angle and XPS measurements showed that C12, C14, and C16 monolayers have a comparably higher quality, while the quality of C10 and C18 monolayers is worse. GIXD revealed that the alkyl monolayers directly attached to the Si were all amorphously structured regardless of their alkyl chain length. The amorphous structure of the alkyl monolayers could be attributed to the rigid Si-C bonding, low quality of hydrogen-terminated silicon substrate, and/or low mobility of physisorbed molecules.
在160摄氏度下，由1 - 癸烯（C10）、1 - 十二碳烯（C12）、1 - 十四碳烯（C14）、1 - 十六碳烯（C16）和1 - 十八碳烯（C18）制备了不同烷基分子链长度直接连接到硅上的烷基有机单层膜。基于水接触角测量、椭偏仪、X射线反射率（XR）、X射线光电子能谱（XPS）和掠入射X射线衍射（GIXD）对这些单层膜进行了表征，以阐明分子链长度对单层膜分子排列和堆积密度的影响。水接触角和XPS测量表明，C12、C14和C16单层膜具有相对较高的质量，而C10和C18单层膜的质量较差。GIXD显示，直接连接到硅上的烷基单层膜无论其烷基链长度如何，均为非晶结构。烷基单层膜的非晶结构可归因于刚性的Si - C键、氢终止硅衬底的低质量和/或物理吸附分子的低迁移率。
