Zn‐based batteries are safe, low cost, and environmentally friendly, as well as delivering the highest energy density of all aqueous battery systems. However, the application of Zn‐based batteries is being seriously hindered by the uneven electrostripping/electroplating of Zn on the anodes, which always leads to enlarged polarization (capacity fading) or even cell shorting (low cycling stability). How a porous nano‐CaCO3 coating can guide uniform and position‐selected Zn stripping/plating on the nano‐CaCO3‐layer/Zn foil interfaces is reported here. This Zn‐deposition‐guiding ability is mainly ascribed to the porous nature of the nano‐CaCO3‐layer, since similar functionality (even though relatively inferior) is also found in Zn foils coated with porous acetylene black or nano‐SiO2 layers. Furthermore, the potential application of this strategy is demonstrated in Zn|ZnSO4+MnSO4|CNT/MnO2 rechargeable aqueous batteries. Compared with the ones with bare Zn anodes, the battery with a nano‐CaCO3‐coated Zn anode delivers a 42.7% higher discharge capacity (177 vs 124 mAh g−1 at 1 A g−1) after 1000 cycles.

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As a promising anode for aqueous batteries, Zn metal shows a number of attractive advantages such as low cost, low redox potential, high capacity, and environmental benignity. Nevertheless, the quick growth of dendrites/protrusions on the “hostless” Zn anodes not only enlarges batteries’ internal resistance but also causes sudden shorting failure by piercing separators. Herein, we report a novel heterogeneous seed method to guide the morphology evolution of plated Zn. The heterogeneous seeds are sputtering-deposited quasi-isolated nano-Au particles (Au-NPs) that enable a uniform and stable Zn-plating/stripping process on the anodes. Tested on Zn|Zn symmetric cells, the Au-nanoparticle (NP) decorated Zn anodes (NA-Zn) demonstrate much better cycling stability than the bare ones (92 vs 2000 h). In NA-Zn|CNT/MnO2 batteries, this heterogeneous seed prolongs the lifetime of the device from ∼480 cycles up to 2000 cycles. This work offers a facile and promising Zn dendrite/protrusion suppressing route for the achievement of long-life Zn-ion batteries.

Zn-ion batteries have been widely investigated due to their low cost, high safety and eco-friendliness. We comprehensively evaluate the performance of oxides (MoO, TiO, and FeO), sulfides (MoS, WS, and MnS) and borides (TiB and ZrB) in zinc ion battery systems. It is found that MnS is a good alternative cathode material with a reversible capacity of 221 mA h g, while the other materials show different behaviours.

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