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.

中文翻译：

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液态金属上MnO2单层的自限电流生长-适用于光催化

液态金属提供了前所未有的化学性能。此处表明，它们可以促进其表面的自限氧化过程，从而使原子薄的金属氧化物得以生长。通过产生原子级薄水合MnO ₂可以举例说明这一要求使用高锰酸根离子与液态镓铟合金（EGaIn）之间的电置换反应。“液态溶液”-“液态金属”过程导致高锰酸盐离子的还原，导致在界面处形成氧化物单层。研究表明，在机械搅拌下会形成液态金属滴，同时，水合的氧化镓和氧化锰片会从界面边界处分层。产生的纳米片封装了金属核，发现该金属核仅由固态铟组成，并且镓从液滴中完全迁移出来。该过程产生核/壳结构，其中壳由堆叠的原子薄纳米片制成。发现所获得的核/壳结构是在模拟太阳辐射下用于降解有机染料的有效光催化剂。这项研究为通过自发界面氧化还原反应对液态金属进行改性和功能化提出了新的研究方向，这对光催化以外的许多应用都具有重要意义。