Horizontally arranged zinc platelet electrodeposits modulated by fluorinated covalent organic framework film for high-rate and durable aqueous zinc ion batteries
Zedong Zhao, Rong Wang, Chengxin Peng, Wuji Chen, Tianqi Wu, Bo Hu, Weijun Weng, Ying Yao, Jiaxi Zeng, Zhihong Chen, Peiying Liu, Yicheng Liu, Guisheng Li, Jia Guo, Hongbin Lu, Zhanhu Guo
Abstract
Abstract Rechargeable aqueous zinc-ion batteries (RZIBs) provide a promising complementarity to the existing lithium-ion batteries due to their low cost, non-toxicity and intrinsic safety. However, Zn anodes suffer from zinc dendrite growth and electrolyte corrosion, resulting in poor reversibility. Here, we develop an ultrathin, fluorinated two-dimensional porous covalent organic framework (FCOF) film as a protective layer on the Zn surface. The strong interaction between fluorine (F) in FCOF and Zn reduces the surface energy of the Zn (002) crystal plane, enabling the preferred growth of (002) planes during the electrodeposition process. As a result, Zn deposits show horizontally arranged platelet morphology with (002) orientations preferred. Furthermore, F-containing nanochannels facilitate ion transport and prevent electrolyte penetration for improving corrosion resistance. The FCOF@Zn symmetric cells achieve stability for over 750 h at an ultrahigh current density of 40 mA cm −2 . The high-areal-capacity full cells demonstrate hundreds of cycles under high Zn utilization conditions.