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Covalent organic frameworks (COFs) are attractive candidates for low-cost potassium-ion battery (PIB) electrode materials due to their inherent porosity, well-organized channel structure, and excellent thermochemical stability. Herein, a Schiff-base COF/carbon nanotubes (TP-COF/CNTs) composite is synthesized by a condensation reaction between 1,3,5-triformylbenzene (TFB) and pphenylenediamine (PPD) on the surface of CNTs as an anode for PIBs. The introduction of CNTs not only assumes the role of a conductive network in improving the kinetics of potassium ions (K + ) but also induces the growth of COFs through π−π interactions, leading to more exposure of more active sites. In consequence, the core−shell-structured TP-COF/CNTs exhibit advanced K storage performance (290 mA h g −1 after 200 cycles at 0.1 A g −1 ) and fine rate capability (169 mA h g −1 at 1 A g −1 ), outperforming most COF materials. Furthermore, X-ray photoelectron spectroscopy, ex situ infrared analysis, and density functional theory calculations indicate that the storage of K + depends on electroactive C�N groups and the π−K + effect. This work supplies PIBs with a promising high-performance anode material and may benefit the development of COFs for PIBs.

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Magnesium‐ion batteries (MIBs) are emerging as potential next‐generation energy storage systems due to high security and high theoretical energy density. Nevertheless, the development of MIBs is limited by the lack of cathode materials with high specific capacity and cyclic stability. Currently, transition metal sulfides are considered as a promising class of cathode materials for advanced MIBs. Herein, a template‐based strategy is proposed to successfully fabricate metal‐organic framework‐derived in‐situ porous carbon nanorod‐encapsulated CuS quantum dots (CuS‐QD@C nanorods) via a two‐step method of sulfurization and cation exchange. CuS quantum dots have abundant electrochemically active sites, which facilitate the contact between the electrode and the electrolyte. In addition, the tight combination of CuS quantum dots and porous carbon nanorods increases the electronic conductivity while accelerating the transport speed of ions and electrons. With these architectural and compositional advantages, when used as a cathode material for MIBs, the CuS‐QD@C nanorods exhibit remarkable performance in magnesium storage, including a high reversible capacity of 323.7 mAh g−1 at 100 mA g−1 after 100 cycles, excellent long‐term cycling stability (98.5 mAh g−1 after 1000 cycles at 1.0 A g−1), and satisfying rate performance (111.8 mA g−1 at 1.0 A g−1).