Co‐MOF derived MoSe ₂ @ CoSe ₂ /N‐doped carbon nanorods as high‐performance anode materials for potassium ion batteries

Abstract

Potassium ion batteries (KIBs) have attracted considerable attention as a nextgeneration large-scale energy storage system. Due to the large diameter of K + ions, developing advanced electrode materials to achieve high-performance KIBs is challenging. In this paper, one-dimensional (1D) hybrid nanostructures comprising a MoSe 2 core and a CoSe 2 /N-doped carbon shell (denoted as MC-Se@NC) are successfully synthesized by thermal treatment of Co-based metal-organic framework (ZIF-67)-coated MoO 3 nanorods. The unique 1D morphology and synergistic effect between the different elements provide sufficient electrochemical reaction sites and facilitate the reaction kinetics. Further, the N-doped carbon coating alleviates the volume fluctuation and pulverization of the active materials during cycling and improves the electrode conductivity. Accordingly, when applied to KIBs, the MC-Se@NC anode delivers a high reversible capacity of 327 mA h g À1 at 0.5 A g À1 after 150 cycles, and remarkable rate capability of 190 mA h g À1 at 2.0 A g À1 . Furthermore, to explore the practical application of MC-Se@NC anode, a K-ion full cell consisting of MC-Se@NC anode and Prussian blue cathode is fabricated and characterized. As a demonstration, a light-emitting diode (LED) is successfully powered by the K-ion full cell. These excellent electrochemical properties of MC-Se@NC present possibilities for the commercialization of KIB-based largescale energy storage systems.

Spaced-Confined Janus Engineering Enables Controlled Ion Transport Channels and Accelerated Kinetics for Secondary Ion Batteries

“…In addition, the distribution of the C element proves the formation of carbon coating and carbon nanotubes. Herein, carbon nanotubes and carbon shell not only provide stable structure and enough space to alleviate the volume expansion effect but also enhance the electrical conductivity. , …”

“…Herein, carbon nanotubes and carbon shell not only provide stable structure and enough space to alleviate the volume expansion effect but also enhance the electrical conductivity. 29,30 To confirm the crystal structure of Janus Co/Co 2 P@CNT-CS refined urchin-like architecture, XRD pattern is shown in S6 and Table S1. In addition, the specific surface area and the pore size distribution of Janus Co/Co 2 P@ CNT-CS, Co, and Co 2 P are shown in Figure S7 and Table S2.…”

Bimetallic-based composites for potassium-ion storage: challenges and perspectives

“…Cobalt (Co), iron (Fe) and molybdenum (Mo) also contribute to the formation of stable solid electrolyte interface (SEI) layers when used as components of ABXs. 78,79 Wang et al prepared Sb 2 MoO 6 /rGO, in which Sb has high capacity and Mo contributes to the formation of a buffer matrix and improves the stability, allowing the material to exhibit excellent cycling performance. 52 Yuan et al synthesized ZnSe-FeSe 2 /rGO in which ZnSe is responsible for providing high capacity while FeSe 2 can enhance the overall electrochemical stability.…”

Enlarged Interlayer Spacing of Marigold-Shaped 1T-MoS2 with Sulfur Vacancies via Oxygen-Assisted Phosphorus Embedding for Rechargeable Zinc-Ion Batteries

“…Molybdenum disulfide (MoS 2 ) is a typical layered transition metal sulfide, and the covalently bonded S-Mo-S layers are stacked together by weak van der Waals forces, which is conducive to the intercalation of foreign guests [ 11 , 12 , 13 , 14 ]. Unfortunately, due to the strong electrostatic interaction between inserted Zn 2+ with a large hydrated radius (4.3 Å) and host structures, Zn 2+ is challenging to intercalate/deintercalate from the host frame, greatly affecting the reversible capability and rate characteristic of MoS 2 as cathodes arousing from its smaller layer spacing and the large inert base with fewer active sites [ 15 , 16 , 17 , 18 ]. Moreover, MoS 2 also has problems such as poor conductivity, poor hydrophilicity, agglomeration, and volume expansion, which limits the application of MoS 2 in ZIBs.…”