Interweaving Covalent Organic Polymer Chains Into Two-Dimensional Networks: Synthesis, Single Crystal Structure, and Application for Stabilizing Lithium Metal Anode

Abstract

Macroscopic weaving has been proven to be the most enduring and effective method for manufacturing fabrics to meet the practical needs of humanity for thousands of years. However, the construction of molecular structures with exquisite topologies and specific properties based on molecular weaving is still in its infancy. Herein, we designed and fabricated a two-dimensional (2D) woven covalent organic polymer (COP) network (named as CityU-46) driven by the dative N→B bonds between the 1,4-bis(benzodioxa-borole)benzene (BACT) and 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (BPT). The complex woven topology of CityU-46 was determined using a single-crystal X-ray diffraction technique, revealing that it features a well-defined two-over and two-under interweaving pattern at the molecular level. Due to its structural merits, CityU-46 can be used as an artificial organic solid-electrolyte interphase layer on the surface of Li metal anodes, significantly improving the stability and long-term performance of lithium metal cells.