Zincophilic ultrathin Zn metal anode enabling uniform deposition and corrosion suppression in aqueous zinc ion batteries

초록

Zn metal anodes are promising for rechargeable aqueous zinc-ion batteries; however, practical deployment requires the use of thin Zn layers to preserve the energy density and suppress dendrite growth and corrosion driven by the hydrogen evolution reaction (HER). Herein, an ultrathin Zn anode (similar to 9 mu m) is constructed with a zincophilic ZnSe layer with a thickness of approximately 100 nm. Electroplating is introduced to form the Zn anode, the deposition time is adjusted to control the thickness, and the resulting thin layer exhibits improved mechanical flexibility. Density functional theory and COMSOL analyses indicate that the ZnSe interphase facilitates interfacial supply of Zn2+, consistent with the observed uniform plating/stripping and low interfacial resistance. ZnSe treatment limits the direct contact between the electrolyte and Zn metal and increases the Zn (002) texture, thereby suppressing HER-induced corrosion. Consequently, when paired with V2O5 cathodes under a low N/P ratio of 2.6 in full cells, the anode maintains a capacity of 160 mAh g(-1) for more than 1500 cycles at 5 A g(-1). In contrast to surface treatment of thick commercial Zn foil, this scalable interfacial engineering strategy for ultrathin Zn metal anodes enables high energy density and long cycle life in practical cells.

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