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The absence of magnetic moments in pristine two-dimensional (2D) semiconducting materials has attracted many research interests. Transition-metal (TM) decoration has been found to be an effective strategy to introduce magnetic moments in non-magnetic 2D semiconductors. However, the stability of TM atoms modified 2D semiconductors has not been well explored. Here, taking 2D Tin (II) sulfide (SnS) monolayer as a prototype, we explored the stability of magnetic semiconductors through this method. In our studies, all possible configurations of TM decoration have been considered, namely, adsorption on the intact surface, S vacancy, and Sn vacancy. Based on the energy gain and electronic analysis, our results revealed that most of the TM atoms will form a cluster, and only several TM atoms can be effectively doped into the SnS monolayer. Furthermore, the band calculations showed that only Mn substitution will give rise to a magnetic semiconductor. Thus, the reported results here provide some hidden information for further realization of the magnetic semiconductors and serve as a paradigm to prepare 2D magnetic semiconductors.

Although additives are widely used in aqueous electrolytes to inhibit the formation of dendrites and hydrogen evolution reactions on Zn anodes, there is a lack of rational design principles and systematic mechanistic studies on how to select a suitable additive to regulate reversible Zn plating/stripping chemistry. Here, using saccharides as the representatives, we reveal that the electrostatic polarity of non‐sacrificial additives is a critical descriptor for their ability to stabilize Zn anodes. Non‐sacrificial additives are found to continuously modulate the solvation structure of Zn ions and form a molecular adsorption layer (MAL) for uniform Zn deposition, avoiding the thick solid electrolyte interphase layer due to the decomposition of sacrificial additives. A high electrostatic polarity renders sucrose the best hydrated Zn2+ desolvation ability and facilitates the MAL formation, resulting in the best cycling stability with a long‐term reversible plating/stripping cycle life of thousands of hours. This study provides theoretical guidance for the screening of optimal additives for high‐performance ZIBs.

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