Yang Guang, Chang Wen-Sheng, Hallinan Daniel T
Florida State University, Aero-Propulsion, Mechatronics & Energy Center, 2003 Levy Avenue, Tallahassee, FL 32310, USA; Florida A&M University - Florida State University College of Engineering, Department of Chemical and Biomedical Engineering, 2525 Potsdammer Street, Tallahassee, FL 32310, USA.
Green Energy & Environment Laboratories/ITRI, Rm. 307B, Bldg. 64, 195, Sec. 4, Chung Hsing Rd., Chutung, Hsinchu 31040, Taiwan, ROC.
J Colloid Interface Sci. 2015 Dec 15;460:164-72. doi: 10.1016/j.jcis.2015.08.054. Epub 2015 Aug 24.
Aqueous citrate-stabilized gold nanoparticles (Au NPs) cannot be directly transferred from water to an immiscible organic solution using short alkyl ligands. However, Au NPs can be transferred from water to a water-organic interface if chemical and mechanical inputs are used to modify the interfacial energy and interfacial area. Ligand exchange can then take place at this interface. After separating the particles from the liquids, they can be transferred to a different organic phase.
Hexane, alkylamine, and acetone were added to aqueous citrate-stabilized Au NPs to form a film at the system interfaces. After removing the liquid phases, Au NPs were readily redispersed into tetrahydrofuran (THF). The size and shape of the transferred Au NPs were evaluated by transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS).
Au NPs with 13nm diameter are readily segregated from water with the aid of short alkylamine ligands. They form a thin film at the water/organic solvent interface, rendering them easy to separate from the liquid phases and possible to redisperse into another organic solvent. After the phase transfer process, Au NPs were functionalized with short amine ligands. In addition, the shape and size of Au NPs were preserved. The short amine-protected Au NPs in THF can stay stable for up to 27days or longer.
使用短链烷基配体时，水相柠檬酸盐稳定的金纳米颗粒（Au NPs）无法直接从水相转移至不混溶的有机溶液中。然而，如果利用化学和机械输入来改变界面能和界面面积，金纳米颗粒能够从水相转移至水 - 有机界面。然后，配体交换可在此界面发生。将颗粒与液体分离后，它们可被转移至另一种有机相中。
将己烷、烷基胺和丙酮添加到水相柠檬酸盐稳定的金纳米颗粒中，以在系统界面形成薄膜。除去液相后，金纳米颗粒很容易重新分散到四氢呋喃（THF）中。通过透射电子显微镜（TEM）和小角X射线散射（SAXS）对转移后的金纳米颗粒的尺寸和形状进行评估。
借助短链烷基胺配体，直径为13nm的金纳米颗粒很容易从水相中分离出来。它们在水/有机溶剂界面形成一层薄膜，使其易于与液相分离，并有可能重新分散到另一种有机溶剂中。经过相转移过程后，金纳米颗粒用短链胺配体进行了功能化。此外，金纳米颗粒的形状和尺寸得以保留。在THF中，短链胺保护的金纳米颗粒可保持稳定长达27天或更长时间。
