Talc as Dynamic Zincophilic Sites Enables Highly Reversible Zinc Metal Anodes.
Yu DengHao GuChengkun LiuZhengquan XiaoMeinan ZhaoZhipeng JiangYongtao LiPublished in: The journal of physical chemistry letters (2024)
Zinc (Zn) dendrite growth poses a significant challenge to the reversibility of zinc metal anodes (ZMAs). Traditional methods using fixed zincophilic sites often suffer from coverage issues and deactivation over time or under high areal capacities. To address this, we introduced Talc into a conventional ZnSO 4 -based electrolyte (BE + Talc), which acts as a dynamic zincophilic site. Talc effectively adsorbs and carries Zn 2+ in the electrolyte, facilitating their co-deposition at the anode. After deposition, Talc re-enters the electrolyte, maintaining its functionality and counteracting the deactivation of static zincophilic sites. This approach resulted in a Zn-Zn symmetric cell using BE + Talc, achieving stable cycling for 200 h under rigorous conditions of 10 mA cm -2 and 5 mAh cm -2 . Additionally, the Zn-Cu half-cell demonstrated over 1200 stable cycles at 5 mA cm -2 and 1 mAh cm -2 . The Zn-NH 4 V 4 O 10 full cell with Talc cycled for 200 cycles under practical conditions (4.5 mg cm -2 , 10 μm Zn foil, and N/P ratio of 3.4) achieved a capacity retention rate of 82.7%. This study highlights the drawbacks of conventional zincophilic sites and presents an effective solution for achieving highly reversible ZMAs.