Modulating Electron Delocalization Structure in Covalent Organic Frameworks Through Conjugation and Hybridization to...

The inherent factors influencing the growth of lithium (Li) dendrites and the kinetics of Li⁺ migration in polymer electrolytes lie in the electron cloud density distribution in the electrolyte. Localized electrons accumulation can trigger the uneven Li⁺ deposition, ultimately leading to battery failure. To address this critical challenge, the concept of p-π conjugation and B-O sp² hybridization is innovatively incorporated into covalent organic frameworks (COFs) to mitigate local interfacial Li⁺ accumulation and improve Li⁺ migration kinetics in electrolytes by electron delocalization. Furthermore, perfluoroalkyl group with virtues of superior electron regulating capabilities and improved electrochemical-window, is strategically grafted to better match high-voltage cathodes. Under the synergistic role of electron regulation, the electrolyte with pπ-sp²-COF significantly improves overall electrochemical performance of solid-state batteries. Thus, regulating electron density via p-π conjugation and B-O sp² hybridization promises to open new avenues for the development of COFs-modified polymer electrolytes in solid-state batteries.