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Aqueous Zn-ion batteries (ZIBs) are considered very promising alternatives to lithium-ion batteries. However, the low reversibility and slow diffusion of zinc ions in the positive electrode limited commercial applications. Herein,...

Iodine is considered to have broad application prospects in the field of electrochemical energy storage. However, the high solubility of I 3 − severely hampers its practical application, and the lack of research on the anchoring mechanism of I 3 − has seriously hindered the development of advanced cathode materials for iodine batteries. Herein, based on the molecular orbital theory, we studied the charge-transfer interaction between the acceptor of I 3− with a σ* empty antibonding orbital and the donor of pyrimidine nitrogen with lone-pair electrons, which is proved by the results of UV−vis absorption spectroscopy, Raman spectroscopy, and density functional theory (DFT) calculations. The prepared dual-ion battery (DIB) exhibits a high voltage platform of 1.2 V, a remarkable discharge-specific capacity of up to 207 mAh g −1 , and an energy density of 233 Wh kg −1 at a current density of 5 A g −1 , as well as outstanding cycle stability (operating stably for 5000 cycles) with a high Coulombic efficiency of 97%, demonstrating excellent electrochemical performance and a promising prospect in stationary energy storage.

Commercialization of aqueous zinc‐metal batteries remains unrealistic due to the substantial dendrite growth and side reaction issues on the zinc anodes. It is highly demanded to develop easy‐to‐handle approaches for constructing stable, dense, as well as homogeneous solid anode/electrolyte interfaces. Herein, the authors construct the zinc anode interface with a close‐packed Zn‐TSA (TSA = thiosalicylate) coordination supramolecular network through the facile and up‐scalable wet‐chemical method. The hydrophobic Zn‐TSA network can block solvated water and establish a solid‐state diffusion barrier to well‐distribute the interfacial Zn2+, thus inhibiting hydrogen evolution and zinc dendrite growth on the anode. Meanwhile, the Zn‐TSA network induces the formation of a uniform and stable solid electrolyte interphase composed of multiple inorganic‐organic compounds. This denser structure can accommodate and self‐heal the crack/degradation of the anode interphase associated with the repeated volume changes, and suppress the generation of detrimental by‐product, Znx(OTF‐)y(OH)2x−y·nH2O. Such a rationally fabricated anode/electrolyte interface further endows the assembled symmetric cells with superior plating/stripping stability for over 2000 h without dendrite formation (at 1 mA cm‐2 and 1 mAh cm‐2). Furthermore, this zinc anode has practical application in the Zn‐MoS2 and Zn‐V2O5 full cells. This study provides a new train of thought for constructing the dense interface of zinc‐metal anode.

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