Hoffman David J, Bechtel Hans A, Huyke Diego A, Santiago Juan G, DePonte Daniel P, Koralek Jake D
Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States.
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California94720, United States.
Langmuir. 2022 Oct 25;38(42):12822-12832. doi: 10.1021/acs.langmuir.2c01724. Epub 2022 Oct 11.
Chemical reactions and biological processes are frequently governed by the structure and dynamics of the interface between two liquid phases, but these interfaces are often difficult to study due to the relative abundance of the bulk liquids. Here, we demonstrate a method for generating multilayer thin film stacks of liquids, which we call liquid heterostructures. These free-flowing layered liquid sheets are produced with a microfluidic nozzle that impinges two converging jets of one liquid onto opposite sides of a third jet of another liquid. The resulting sheet consists of two layers of the first liquid enveloping an inner layer of the second liquid. Infrared microscopy, white light reflectivity, and imaging ellipsometry measurements demonstrate that the buried liquid layer has a tunable thickness and displays well-defined liquid-liquid interfaces and that this inner layer can be only tens of nanometers thick. The demonstrated multilayer liquid sheets minimize the amount of bulk liquid relative to their buried interfaces, which makes them ideal targets for spectroscopy and scattering experiments.
化学反应和生物过程常常受两个液相之间界面的结构和动力学支配，但由于大量液体的相对丰度，这些界面往往难以研究。在此，我们展示了一种生成液体多层薄膜堆叠的方法，我们将其称为液体异质结构。这些自由流动的分层液体片是通过微流体喷嘴产生的，该喷嘴将一种液体的两股汇聚射流撞击到另一种液体的第三股射流的相对两侧。所得的片由两层第一种液体包裹着第二层液体的内层组成。红外显微镜、白光反射率和成像椭偏测量表明，埋入的液体层具有可调厚度，并显示出清晰的液 - 液界面，并且该内层厚度仅为几十纳米。所展示的多层液体片相对于其埋入的界面将大量液体的量减至最少，这使其成为光谱学和散射实验的理想目标。
