Design and construction of high-capacity covalent organic frameworks (COFs)-based electrode materials and research on the energy storage mechanism still present challenges. In this study, an anthraquinone-derived porous covalent organic framework (DAAQ-COF) with dual-redox active sites of CN and C O groups is synthesized by the condensation of 2,6-diaminoanthraquinone (DAAQ) and 1,3,5-benzenetricarboxaldehyde (Tb).The extra CO groups contribute to the increase of the theoretical capacity of DAAQ-COF. The porous structure provides an open channel for ionic transportation and exposes storage sites for Li + . As the anode material for lithium-ion batteries (LIBs), the DAAQ-COF shows remarkable performance and continuous "activation" behavior with a high discharge capacity of 787 mA h g −1 after 500 cycles at 1 A g −1 . On the basis of the characterization of the cycled electrode, we speculate that lithium ions absorption/desorption due to the layered structure contributes to the partial capacity of DAAQ-COF. Meanwhile, the gradual lithiation of not only the CN and CO bonds but also the aromatic CC bonds results in the increasing exceptional capacity. Therefore, a combined charge storage mechanism including multiredox processes and an ions absorption/desorption process is proposed for the DAAQ-COF. This work deepens the understanding of the energy storage mechanism of high-capacity COFs.

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