The practical applications of Mg metal anodes in rechargeable magnesium batteries (RMBs) have been seriously hindered due to the unstable anode interface. Herein, a simple and hyper-efficient hydrolysis of metal chloride strategy is proposed to obtain a dense layer of artificial SEI on the surface of the Mg anode. Based on the variations of relative compactness density (rρ_c), the morphology and electrochemical properties of the artificial SEI layer can be precisely regulated. Moreover, the surface-reconstructed In/MgCl₂@Mg electrode can achieve an ultralong cycle life of 1500 cycles at a current density of 3 mA cm^–2 and 1 mA h cm^–2 as well as a low overpotential (0.25 V). Consequently, a stable cycle capacity can also be maintained at 1C after 1000 cycles in full cell configurations, matching with the Mo₆S₈ cathode. This study provides a novel design concept and quantitative criteria for the specific preparation of efficient Mg anodes.

中文翻译：

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深入了解用于高度可逆性镁金属负极的紧凑型人工 SEI 的超高效构建


由于负极界面不稳定，Mg金属负极在可充电镁电池（RMBs）中的实际应用受到严重阻碍。在此，提出了一种简单且超高效的金属氯化物水解策略，以在 Mg 阳极表面获得致密的人工 SEI 层。基于相对致密密度 （rρ_c） 的变化，可以精确调节人工 SEI 层的形态和电化学性质。此外，表面重构的 In/MgCl₂@Mg 电极可以在 3 mA cm^–2 和 1 mA h cm^–2 的电流密度以及低过电位 （0.25 V） 下实现 1500 次循环的超长循环寿命。因此，在全电池配置中，在 1000 次循环后，也可以将稳定的循环容量保持在 1C，与 Mo₆S₈ 阴极相匹配。本研究为高效镁负极的具体制备提供了一种新颖的设计理念和定量标准。