Kim Ji-Hye, Kim Sooyoung, Dickey Michael D, So Ju-Hee, Koo Hyung-Jun
Department of Energy and Chemical Engineering, Seoul National University of Science & Technology, 232 Gongneung-ro, Nowon-gu, Seoul, 01811, Republic of Korea.
Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695, USA.
Nanoscale Horiz. 2024 Jun 24;9(7):1099-1119. doi: 10.1039/d4nh00067f.
Gallium-based liquid metals (GaLMs) are promising for a variety of applications-especially as a component material for soft devices-due to their fluidic nature, low toxicity and reactivity, and high electrical and thermal conductivity comparable to solid counterparts. Understanding the interfacial properties and behaviors of GaLMs in different environments is crucial for most applications. When exposed to air or water, GaLMs form a gallium oxide layer with nanoscale thickness. This "oxide nano-skin" passivates the metal surface and allows for the formation of stable microstructures and films despite the high-surface tension of liquid metal. The oxide skin easily adheres to most smooth surfaces. While it enables effective printing and patterning of the GaLMs, it can also make the metals challenging to handle because it adheres to most surfaces. The oxide also affects the interfacial electrical resistance of the metals. Its formation, thickness, and composition can be chemically or electrochemically controlled, altering the physical, chemical, and electrical properties of the metal interface. Without the oxide, GaLMs wet metallic surfaces but do not wet non-metallic substrates such as polymers. The topography of the underlying surface further influences the wetting characteristics of the metals. This review outlines the interfacial attributes of GaLMs in air, water, and other environments and discusses relevant applications based on interfacial engineering. The effect of surface topography on the wetting behaviors of the GaLMs is also discussed. Finally, we suggest important research topics for a better understanding of the GaLMs interface.
基于镓的液态金属（GaLMs）因其流体性质、低毒性和反应性以及与固态对应物相当的高电导率和热导率，在各种应用中具有广阔前景，特别是作为软设备的组成材料。了解GaLMs在不同环境中的界面性质和行为对于大多数应用至关重要。当暴露于空气或水中时，GaLMs会形成纳米级厚度的氧化镓层。这种“氧化物纳米皮肤”钝化了金属表面，尽管液态金属具有高表面张力，但仍能形成稳定的微观结构和薄膜。氧化物皮肤很容易附着在大多数光滑表面上。虽然它使GaLMs能够进行有效的印刷和图案化，但也可能使金属难以处理，因为它会附着在大多数表面上。氧化物还会影响金属的界面电阻。其形成、厚度和组成可以通过化学或电化学方式控制，从而改变金属界面的物理、化学和电学性质。没有氧化物时，GaLMs会润湿金属表面，但不会润湿诸如聚合物等非金属基材。底层表面的形貌进一步影响金属的润湿特性。本综述概述了之GaLMs在空气、水和其他环境中的界面属性，并讨论了基于界面工程的相关应用。还讨论了表面形貌对GaLMs润湿行为的影响。最后，我们提出了一些重要的研究课题，以便更好地理解GaLMs界面。
