Cu₇Te₄ as an Anode Material and Zn Dendrite Inhibitor for Aqueous Zn‐Ion Battery

Abstract

Abstract Zn metal is a promising anode material for high‐energy‐density aqueous batteries, but it is plagued by dendrite, low stripping/plating efficiency, and inevitable depletion of active Zn. Herein, a low‐intercalation‐potential material, Cu 7 Te 4 , is reported as both an anode material and Zn dendrite inhibitor for aqueous Zn batteries. A low plateau of 0.2 V (vs Zn 2+ /Zn), high capacity of 216 mA h g –1 , and superior cyclability over 4200 cycles can be realized by Cu 7 Te 4 anode. Moreover, when Zn is modified with Cu 7 Te 4 layer, a hybrid anode based on “intercalation–deposition” mechanism can be ingeniously developed, in which Zn 2+ ions are sequentially inserted into Cu 7 Te 4 and uniformly deposed on Zn at successive low potential. A battery built on such a mechanism sustains more than 1000 h and 1000 times in comparison to less than 100 h and 350 times of a bare Zn. Furthermore, an aqueous “rocking–chair” Cu 7 Te 4 //ZnI 2 Zn‐ion full battery is further demonstrated, which can realize energy densities of 65.3 Wh kg –1 and 86% capacity retentions after 10 000 cycles. This research contributes to a stable anode material for aqueous Zn batteries and provides an effective strategy to address the Zn dendrite.