近日，美国康奈尔大学Nicholas L. Abbott团队研究了具有可变形和双稳微畴的双相液体。2025年7月16日出版的《自然》杂志发表了这项成果。

由两相共存组成的液体可以形成一系列稳定和亚稳态，包括湿膜、液滴和线。然而，允许这些形态之间快速可逆转变的过程很难实现，因为快速形状变化所需的物理性质（例如，低界面张力或粘度）提供了导致短暂状态的松弛途径。长寿命微畴态的完全可逆形成将扩展双相液体（例如，可调光学超材料）的动态特性。

研究组报告了由各向同性油和液晶油组成的双相液体系统的变形和双稳态微畴的发现。各向同性油在固体表面和上覆的液晶相之间形成稳定的润湿膜（“原始”形状），当暴露在低频（10Hz）的瞬态（<1s）交流电场中时，转变为长寿命（>24h）的球形畴（“临时”形状），由液晶中的拓扑缺陷稳定。随后施加高频（1kHz）的交流电场会触发液晶中形成孤子，从而产生动力学途径，导致分散的球形畴非常迅速地（<3s）聚合并恢复原始形状（湿膜）。

研究组展示了双相系统的不同光学状态之间的快速可逆切换，每个状态都可以在没有连续应用的情况下持续存在，它们提供了长期以来在液体薄膜中寻求的光学特性的组合。该研究报道的完全可逆和长寿命的乳化液形成在材料合成、微化学系统和可调谐光学超材料（例如，控制通过窗口的光的可见度和透射率）方面前景广阔。

附：英文原文

Title: Biphasic liquids with shape-shifting and bistable microdomains

Author: Roh, Sangchul, Ha, Youlim, Abbott, Nicholas L.

Issue&Volume: 2025-07-16

Abstract: Liquids comprising two coexisting phases can form a range of stable and metastable states, including wetting films, droplets and threads1,2,3. Processes that permit rapid and reversible transformations between these morphologies, however, have been difficult to realize because physical properties required for rapid shape change (for example, low interfacial tension or viscosity) provide pathways for relaxation that result in short-lived states. Fully reversible formation of long-lived microdomain states would expand the palette of properties that can be accessed dynamically using biphasic liquids (for example, tunable optical metamaterials). Here we report the discovery of shape-shifting and bistable microdomains of a biphasic liquid system consisting of an isotropic oil and a liquid crystalline oil. The isotropic oil forms stable wetting films (‘original’ shape) between solid surfaces and an overlying liquid crystal phase, and, when exposed to a transient (<1s) a.c. electric field at low frequency (10Hz), transforms into long-lived (>24h) spherical domains (‘temporary’ shape) stabilized by topological defects in the liquid crystal1,4,5. Subsequent application of an a.c. electric field of high frequency (1kHz) triggers solitons to form in the liquid crystal6,7,8, creating kinetic pathways that lead to remarkably rapid (<3s) coalescence of the dispersed spherical domains and recovery of the original shape (wetting film)1,8,9. We show rapid and reversible switching between distinct optical states of the biphasic system, with each state persisting without continuous application of the field, thus providing a combination of optical properties long sought in thin liquid films10,11,12,13,14,15,16,17. The fully reversible and long-lived emulsion formation reported here appears promising for materials synthesis, microchemical systems and tunable optical metamaterials (for example, to control visibility and transmittance of light through windows)17,18,19,20,21.

DOI: 10.1038/s41586-025-09279-2

Source: https://www.nature.com/articles/s41586-025-09279-2