CAJ | 학술논문

以和频(SFG)振动光谱技术探测了正十二硫醇(DDT)在不同受限状态下的分子振动信号,包括金属基底上的自组装单层(SAM)分子,放置在二氧化硅基底上的表面DDT化的金纳米粒子以及金纳米粒子的甲苯溶液。在三种状态下都探测到了来自于DDT分子的振动光谱,振动光谱的区别提供了在不同受限态下DDT分子的结构信息。在金属基底上DDT分子排列规整,放置在二氧化硅基底上的金纳米粒子表面的DDT分子具有一定的柔性,在空气-甲苯溶液界面金纳米粒子表面的DDT分子高度无序。此外,光谱实验显示,金纳米粒子表面的分子振动信号产生了局域场增强的效应,相对于金基底上的自组装单层分子而言,增强系数为102-103,取决于光谱的偏振组合。
이화빈(SFG)진동광보기술탐측료정십이류순(DDT)재불동수한상태하적분자진동신호,포괄금속기저상적자조장단층(SAM)분자,방치재이양화규기저상적표면DDT화적금납미입자이급금납미입자적갑분용액。재삼충상태하도탐측도료래자우DDT분자적진동광보,진동광보적구별제공료재불동수한태하DDT분자적결구신식。재금속기저상DDT분자배렬규정,방치재이양화규기저상적금납미입자표면적DDT분자구유일정적유성,재공기-갑분용액계면금납미입자표면적DDT분자고도무서。차외,광보실험현시,금납미입자표면적분자진동신호산생료국역장증강적효응,상대우금기저상적자조장단층분자이언,증강계수위102-103,취결우광보적편진조합。
The molecular vibrational signals of n-dodecanethiol (DDT) were detected in different confined states using sum frequency generation (SFG) vibrational spectroscopy. Samples with three different confined states were used, including a self-assembled monolayer (SAM) of DDT molecules on a gold (Au) substrate, DDT surface-functionalized Au nanoparticles on a silica substrate, and surface-functionalized Au nanoparticles dispersed in a toluene solution. The vibrational spectra of the DDT molecules were successful y captured for al three samples, and the spectral differences provided evidence of the different confined structures. On the Au substrate, the DDT molecules orderly packed together;on the silica substrate, the DDT molecules attached to the Au nanoparticle surfaces were somehow flexible;and at the air-toluene interface, the DDT molecules attached to the Au nanoparticle surfaces were highly disordered. The spectral analysis indicated that the molecular vibrational signals generated from the Au nanoparticle surfaces were enhanced because of the localized enhanced fields near the Au nanoparticle surfaces, with the enhancement factors of 102-103 over the SAM of DDT molecules on the Au substrate, depending on the selected polarization combination.