Mediating Triple Ions Migration Behavior via a Fluorinated Separator Interface toward Highly Reversible Aqueous Zn Batteries
Fang Shen, He Du, Hongyu Qin, Zongwu Wei, Wei Kuang, Nan Hu, Wensong Lv, Zhihui Yi, Dan Huang, Zhengjun Chen, Huibing He
Abstract
Abstract Rampant dendrite growth, electrode passivation and severe corrosion originate from the uncontrolled ions migration behavior of Zn 2+ , SO 4 2− , and H + , which are largely compromising the aqueous zinc ion batteries (AZIBs) performance. Exploring the ultimate strategy to eliminate all the Zn anode issues is challenging but urgent at present. Herein, a fluorinated separator interface (PVDF@GF) is constructed simply by grafting the polyvinylidene difluoride (PVDF) on the GF surface to realize high‐performance AZIBs. Experimental and theoretical studies reveal that the strong interaction between C─F bonds in the PVDF and Zn 2+ ions enables evenly redistributed Zn 2+ ions concentration at the electrode interface and accelerates the Zn transportation kinetics, leading to homogeneous and fast Zn deposition. Furthermore, the electronegative separator interface can spontaneously repel the SO 4 2− and anchor H + ions to alleviate the passivation and corrosion. Accordingly, the Zn|Zn symmetric cell with PVDF@GF harvests a superior cycling stability of 500 h at 10 mAh cm −2 , and the Zn|VOX full cell delivers 76.8% capacity retention after 1000 cycles at 2 A g −1 . This work offers an all‐round solution and provides new insights for the design of advanced separators with ionic sieve function toward stable and reversible Zn metal anode chemistry.