Unleashing the potential of it-conjugation in organic framework materials for electrochemical energy storage and conversion

Conjugation is an electronic phenomenon in a system where the distribution of it-electrons (or p-electrons) changes due to interactions between atoms in the conjugated structure. The presence of conjugated systems not only has a great impact on the physical properties, such as the ultraviolet absorption spectra, fluorescence spectra, nuclear magnetic resonance, but also plays an important part on the reactivity of the compounds. Conjugated systems composed of different atoms or groups exhibit different degrees of conjugation effects. In this manuscript, the effects of different kinds of it-conjugated structures on organic framework materials are summarized, including it-it, p-it and d-it conjugation. It focuses on recent advancements in the application of energy storage and conversion (ESC) of metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) incorporating with it-conjugated structures. Lastly, the opportunities and challenges involved in the structural design and application of it-conjugation in the near future are proposed.