Zinc metal is considered as one of the best anode choices for rechargeable aqueous Zn-based batteries due to its high specific capacity, abundance, and safety. However, dendrite and corrosion issues remain a challenge for this system. Herein, sieve-element function (selective channel of Zn 2+ ) and uniform-pore distribution (≈3.0 nm) of a kaolin-coated Zn anode (KL-Zn) is proposed to alleviate these problems. Based on the artificial Zn metal/electrolyte interface, the KL-Zn anode not only ensures dendritefree deposition and long-time stability (800 h at 1.1 mA h cm −2 ), but also retards side reactions. As a consequence, KL-Zn/MnO 2 batteries can deliver high specific capacity and good capacity retention as well as a reasonably well-preserved morphology (KL-Zn) after 600 cycles at 0.5 A g −1 . This work provides a deep step toward high-performance rechargeable Zn-based battery system.

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Corrosion and dendritic deposition have been the long-standing interfacial challenges of Zn anode, resulting in the deterioration of the aqueous zinc-based batteries. Herein, the surface of Zn metal anode is pioneeringly reconstructed by a cerium-based conversion film (Zn@CCF) through a chemical conversion method. Faster growth of the film in the vicinity of zinc grain boundaries significantly prevents the substrate from genetic micro-corrosion that leads to catastrophic damage. The affinity of the film toward zinc facilitates a low nucleation barrier and smooth zinc deposition. Consequently, Zn@CCF enables long-term lifespan (1200 h) with low polarization (≈60 mV) at 4.4 mA cm −2 , which also maintains good capacity retention and excellent cycling stability of Zn@CCF/MnO 2 full cells. This facile and effective approach helps suppress Zn dendrite formation and brings forward the significance of surface reconstruction of the Zn metal anode for corrosion inhibition, which can be potentially applied to other metal anodes in aqueous energy storage systems.

Many optimization strategies have been employed to stabilize zinc anodes of zinc-ion batteries (ZIBs). Although these commonly used strategies can improve anode performance, they simultaneously induce specific issues at the same time. In this study, through the combination of structural design, interface modification, and electrolyte optimization, an ‘all-in-one’ (AIO) electrode was developed. Compared to the three-dimensional (3D) anode in routine liquid electrolytes, the new AIO electrode can greatly suppress gas evolution and the occurrence of side reactions induced by active water molecules, while retaining the merits of a 3D anode. Moreover, the integrated AIO strategy achieves a sufficient electrode/electrolyte interface contact area, so that the electrode can promote electron/ion transfer, and ensure a fast and complete redox reaction. As a result, it achieves excellent shelving-restoring ability (60 h, four times) and 1200 cycles of long-term stability without apparent polarization. When paired with two common cathode materials used in ZIBs (α-MnO2 and NH4V4O10), full batteries with the AIO electrode demonstrate high capacity and good stability. The strategy of the ‘all-in-one’ architectural design is enlightened to solve the issues of zinc anodes in advanced Zn-based batteries.

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A Zn anode can offset the low energy density of a flow battery for a balanced approach toward electricity storage. Yet, when targeting inexpensive, long‐duration storage, the battery demands a thick Zn deposit in a porous framework, whose heterogeneity triggers frequent dendrite formation and jeopardizes the stability of the battery. Here, Cu foam is transferred into a hierarchical nanoporous electrode to homogenize the deposition. It begins with alloying the foam with Zn to form Cu5Zn8, whose depth is controlled to retain the large pores for a hydraulic permeability ≈10−11 m2. Dealloying follows to create nanoscale pores and abundant fine pits below 10 nm, where Zn can nucleate preferentially due to the Gibbs–Thomson effect, as supported by a density functional theory simulation. Morphological evolution monitored by in situ microscopy confirms uniform Zn deposition. The electrode delivers 200 h of stable cycles in a Zn–I2 flow battery at 60 mAh cm−2 and 60 mA cm−2, performance that meets practical demands.