The booming of aqueous zinc-ion batteries (AZIBs) draws the researchers' attention to issues of zinc metal anodes, such as uncontrollable dendrite growth, corrosion, and volume effects. Zinc powder anode is more suitable for the industrial application of AZIBs than the widely used zinc foil anode due to its low cost, tunability and processability. However, the related solutions are rarely studied because the above issues of zinc metal anode are more serious in zinc powder anode. Herein, for the first time, we design a semi-solid zinc slurry anode consisting of zinc powder and zincophilic tin additive dispersed in a conductive elastic rheological network. Zinc can be deposited homogeneously on the dispersed tin particles, which avoids agglomerative zinc deposition and alleviates volume change during repeated zinc stripping/plating. Moreover, the practical application of the full cell with slurry is very promising since its operating life can be easily extended by facile slurry renewal.

Aqueous zinc‐ion battery is regarded as one of the promising devices for large‐scale energy storage systems owing to its high safety, cost‐effectiveness, and competitive electrochemical properties. However, the dendrite growth on zinc metal anodes dramatically hinders its further practical applications, and the internal mechanism of dendrite evolution is still unclear. The introduction of a protective layer on the anode interface is an effective method to avoid zinc dendrite growth. Herein, a two‐dimensional (2D) atomic surface diffusion mechanism is proposed to reveal the evolution of zinc deposition from tiny protrusion to dendrite under uneven electric and ionic fields. Further, the conductive copper nitride (CN) protective layer is constructed on the zinc metal anode by a facile and scalable magnetron sputtering approach. Their protective layer possesses a high zinc affinity and high diffusion barrier for zinc atom migration, leading to spacious nucleation, and uniform zinc deposition, thus significantly boosting the electrochemical stability. For the first time, the role of the restricted 2D atomic surface diffusion mechanism in inhibiting the formation of zinc tiny protrusion that induces uneven electric and ionic fields is revealed. This work can provide a novel insight for future research on dendrite‐free zinc metal anodes by interfacial modification.

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Aqueous zinc‐ion batteries are inherently safe, but the severe dendrite growth and corrosion reaction on zinc anodes greatly hinder their practical applications. Most of the strategies for zinc anode modification refer to the research of lithium metal anodes on surface regulation without considering the intrinsic mechanisms of zinc anode. Herein, we first point out that surface modification cannot permanently protect zinc anodes due to the unavoidable surface damage during the stripping process by solid–liquid conversion. A bulk‐phase reconstruction strategy is proposed to introduce abundant zincophilic sites both on the surface and inside the commercial zinc foils. The bulk‐phase reconstructed zinc foil anodes exhibit uniform surfaces with high zincophilicity even after deep stripping, significantly improving the resistance to dendrite growth and side reactions. Our proposed strategy suggests a promising direction for the development of dendrite‐free metal anodes for practical rechargeable batteries with high sustainability.

Aqueous zinc‐ion batteries (AZIBs) have drawn the attention of numerous researchers owing to their high safety and cost‐effectiveness. However, the dendrite growth and side reactions of the zinc (Zn) anodes limit their further practical applications. Herein, a porous amorphous silicon nitride protective layer with high zincophobicity is constructed on the Zn anode surface, which can guide the uniform stripping/plating of Zn2+ underneath the protective layer through its isotropic Zn affinity to alleviate the growth of dendrites and by‐products. As a result, the amorphous silicon nitride‐protected Zn anode can maintain a stable Coulombic efficiency (CE) of 98.8% and low voltage hysteresis for 710 cycles in the half cell. The full cell with the as‐prepared Zn anode can deliver excellent electrochemical performances (89.0% capacity retention and 144.4 mAh g−1 discharge capacity after 1000 cycles at 4 A g−1). This work reveals the key role of uniform metal affinity induced by the amorphous materials in the interface modification of metal anodes, which is instructive for the design of stable metal anodes.