Vanadium Oxide Intercalated with Conductive Metal–Organic Frameworks with Dual Energy‐Storage Mechanism for High Capacity and High‐Rate Capability Zn Ion Storage

Abstract

Abstract Vanadium oxides (VO x ) feature the potential for high‐capacity Zn 2+ storage, which are often preintercalated with inert ions or lattice water for accelerating Zn 2+ migration kinetics. The inertness of these preintercalated species for Zn 2+ storage and their incapability for conducting electrons, however, compromise the capacity and rate capability of VO x . Herein, Ni‐BTA, a 1D conductive metal–organic framework (c‐MOF), is intercalated into the interlayer space of VO x by coordinating organic ligands with preinserted Ni 2+ . The intercalated Ni‐BTA improves the conductivity of VO x by π –d conjugation, facilitates Zn 2+ migration by enlarging its interlayer spacing, and stabilizes the crystal structure of VO x as interlayer pillars, thus simultaneously enhancing the material's rate capability and cycling stability. Meanwhile, a dual reaction mechanism of Zn 2+ storage, i.e., the redox of V 5+ /V 3+ in VO x and the rearrangement of chemical bonds (CN/CN) in Ni‐BTA, collaboratively contributes to an enhanced capacity. Consequently, this Ni‐BTA‐intercalated VO x material exhibits a high Zn 2+ storage capacity of 464.2 mAh g −1 at 0.2 A g −1 and an excellent rate capability of 272.5 mAh g −1 at 5 A g −1 . This work provides a general strategy for integrating c‐MOFs with inorganic cathode materials to achieve high‐capacity and high‐rate performance.