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Exploring and controlling surface tension‐driven phenomena in liquid metals may lead to unprecedented possibilities for next‐generation microfluidics, electronics, catalysis, and materials synthesis. In pursuit of these goals, the impact of minor constituents within liquid alloys is largely overlooked. Herein, it is showed that the presence of a fraction of solute metals such as tin, bismuth, and zinc in liquid gallium can significantly influence their electrocapillarity and electrochemistry. The instability‐driven fractal formation of liquid alloy droplets is investigated with different solutes and reveals the formation of distinctive non‐branched droplets, unstable fractals, and stable fractal modes under controlled voltage and alkaline solution conditions. In their individually unique fractal morphology diagrams, different liquid alloys demonstrate significantly shifted voltage thresholds in transition between the three fractal modes, depending on the choice of the solute metal. Surface tension measurements, cycle voltammetry and surface compositional characterizations provide strong evidence that the minor alloy components drastically alter the surface tension, surface electrochemical oxidation, and oxide dissolution processes that govern the droplet deformation and instability dynamics. The findings that minor components are able to regulate liquid alloys' surface tensions, surface element distributions and electrochemical activities offer great promises for harnessing the tunability and functionality of liquid metals. [ABSTRACT FROM AUTHOR]

Liquid metals provide new dimensions for controlling and governing of reactions. The concept of freely moving metal solutes in liquid metals can be potentially used for enhancing and tuning interfacial reactions. In this work, zinc (Zn), as the solute metal is shown that, can move to the interface, enriching the interfacial area for the efficient synthesis of highly crystalline and porous zeolitic imidazolate framework‐8 (ZIF‐8). The highest rate of reaction is illustrated, and the best quality ZIF‐8, are obtained when a eutectic liquid metal system of Zn with gallium (Ga), containing 3.6 wt.% of Zn, is implemented. It is computationally shown that a combination of Ga activation and freely moving Zn leads to the highest reaction rate and better coordination with organic linkers. The comparisons with solid samples and non‐eutectic systems of Ga liquid demonstrate the advantages of eutectic mix. The work can be expanded to a variety of future interfacial reactions of zeolite imidazole frameworks for commercial scale up. [ABSTRACT FROM AUTHOR]

The nascent field of liquid metals, metals, and alloys of low melting points has provided opportunities for synthesizing low-dimensional materials. Located between transition- and non-metals in the periodic table, post-transition elements exhibit unique properties in particular low melting points. Taking on a liquid form at low temperature, post-transition liquid metals can be used as solvents for metallic solutes. The enigmatic surface of liquid metals is also ultra-active and smooth, offering opportunities for fabricating and templating two-dimensional (2D) films. So far, various 2D materials have been harvested from the surface of liquid metals including 2D metal compounds and nonmetallic materials. Utilizing different extraction and transfer techniques, the produced 2D films can be uniformly deposited on desired substrates at large lateral dimensions. Here, we present a comprehensive overview of the fundamentals underlying post-transition-elements-based liquid metals and alloys and explain the effect of atomic level electron configurations on their characteristics. We discuss the key physical properties of liquid metals including the origin of their low melting points and their high thermal and electrical conductivities. We illustrate their boundary-induced layering and oxidation as essential traits for creating 2D films. Afterward, the interfacial synthesis of 2D materials is depicted with the discussion of surface oxidation, reduction and exfoliation. We present different types of devices using liquid metal-induced 2D synthesis processes, including field-effect transistors, optoelectronic devices, systems that use 2D dielectric and conductive layers, and piezoelectric devices. Eventually, we discuss future prospects and outline how liquid metals can contribute to exciting future applications. [ABSTRACT FROM AUTHOR]

Liquid–liquid interfaces of liquid alloys with electrolytic solutions present fertile platforms for realizing exciting interfacial phenomena that can be devised to process alloys and produce nanomaterials. Here, such an interface is established by immersing a gallium–bismuth binary liquid alloy into aqueous electrolytes. It is shown that the application of a negative voltage to this interface results in a rapid and complete liberation of bismuth nanostructures from liquid gallium. The set of conditions that govern the chemistry of the interface can be adjusted to control the oxidation state, morphology, and crystal structure of the expelled bismuth. By changing the conditions; nanotubular, atomically thin plates, and sea‐urchin‐shaped bismuth oxide morphologies are obtained. The process can also control the crystal phase of bismuth oxide as monoclinic (α), tetragonal (β), or body‐centered cubic (γ). The addition of ascorbic acid to the electrolyte is observed to prevent the oxidation of the expelled entities, resulting in bismuth metal nanoparticles. Ab initio molecular dynamics and computational fluid dynamics simulations are performed to elucidate this rapid phase separation at the interface. This knowledge will potentially lead to new pathways for using alloys as reaction media to refine metals while simultaneously producing nanomaterials for various applications. [ABSTRACT FROM AUTHOR]

Liquid metals offer unprecedented chemistry. Here it is shown that they can facilitate self‐limiting oxidation processes on their surfaces, which enables the growth of metal oxides that are atomically thin. This claim is exemplified by creating atomically thin hydrated MnO2 using a Galvanic replacement reaction between permanganate ions and a liquid gallium–indium alloy (EGaIn). The "liquid solution"–"liquid metal" process leads to the reduction of the permanganate ions, resulting in the formation of the oxide monolayer at the interface. It is presented that under mechanical agitation liquid metal droplets are established, and simultaneously, hydrated gallium oxides and manganese oxide sheets delaminate themselves from the interfacial boundaries. The produced nanosheets encapsulate a metallic core, which is found to consist of solid indium only, with the full migration of gallium out of the droplets. This process produces core/shell structures, where the shells are made of stacked atomically thin nanosheets. The obtained core/shell structures are found to be an efficient photocatalyst for the degradation of an organic dye under simulated solar irradiation. This study presents a new research direction toward the modification and functionalization of liquid metals through spontaneous interfacial redox reactions, which has implications for many applications beyond photocatalysis. [ABSTRACT FROM AUTHOR]