The effects of PEGylated gold nanoparticles (AuNP) colloidally dispersed in ethanol and methanol–ethanol 4 : 1 on solvent solidification induced by hydrostatic pressure are investigated. We have determined the colloid solidification pressure as a function of gold molar concentration in the 0–12 mM range for three nanoparticle sizes. We show that the solvent solidification pressure does not depend on the AuNP size or its specific surface area. It decreases linearly with the total amount of gold up to a 25% reduction of its initial value. Its dependence on the molar concentration of gold in the colloid correlates with the concentration of PEG-SH molecules. On the other hand, Raman spectroscopy shows that the crystalline solid into which AuNP colloids transform under pressure is the same as that into which pure alcohols transform. In addition, the variation of the AuNP plasmonic resonance with pressure allows us to determine the pressure dependence of the density of ethanol in both its liquid and crystalline phases.

中文翻译：

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聚乙二醇化金纳米粒子对醇类固化的影响

研究了胶体分散在乙醇和甲醇-乙醇 4:1 中的聚乙二醇化金纳米粒子 (AuNP) 对静水压诱导的溶剂凝固的影响。我们确定了三种纳米颗粒尺寸的胶体凝固压力与金摩尔浓度在 0-12 mM 范围内的函数关系。我们表明，溶剂固化压力并不取决于 AuNP 的尺寸或其比表面积。它随着黄金总量线性下降，最多比初始值减少 25%。它对胶体中金摩尔浓度的依赖性与 PEG-SH 分子的浓度相关。另一方面，拉曼光谱表明AuNP胶体在压力下转化成的结晶固体与纯醇转化成的结晶固体相同。此外，AuNP 等离子体共振随压力的变化使我们能够确定乙醇在液相和晶相中密度的压力依赖性。