Zn-MOF-74-Derived Carbon Nanorods as an Efficient Se Host for K-Se Batteries

Abstract

Potassium-selenium (K-Se) battery systems have been drawing wide attention owing to their potential for mass production. Despite the great efforts that have been made in the research of this battery system, its sluggish reaction kinetics and severe polyselenide dissolution remain huge challenges. In this paper, the Zn-MOF-74-derived carbon nanorods are designed as a host for Se (denoted as Se@HCR). Thanks to the rich oxygen-containing groups and Zn in the metal–organic framework of Zn-MOF-74, the derived hexagonal prism-like carbon nanorods (HCR) possess abundant interconnected micropores. The obtained HCR carbon matrix shows high conductivity and structural robustness, bringing about better Se utilization, higher transfer rate, and less frequent polyselenide shuttle. It is also able to adapt the volumetric change of Se and deliver outstanding electrochemical performance. In consequence, the obtained Se@HCR delivers a high reversible capacity of 498.7 mAh g–1 after 200 cycles at 0.1 C and 252.4 mAh g–1 after 500 cycles at 1 C and exhibits a rate performance of 291.5 mAh g–1 at 2 C. In conclusion, Zn-MOF-74-derived carbon rods are a promising chalcogenide alloy cathode material host due to their unique hierarchical porosity and convenient preparation.

Double design of host and guest synergistically reinforces the Na-ion storage of sulfur cathodes

“…S1 and S2, † in good accordance with the results of a previous study. 21 The precursor is thermally treated to form porous carbon nanorods under an insert atmosphere (Fig. S3 and S4 † ).…”

Constructing ultra-stable, high-energy, and flexible aqueous zinc-ion batteries using environment-friendly organic cathodes

“…More importantly, organic cathodes are environmentally friendly, renewable, abundant in raw materials, and have high structural tunability, which makes them a research hotspot at present. 13,14…”

Covalent organic frameworks and their composites for rechargeable batteries

“…), covalently bonded, and structurally long-range ordered. 14–17 Due to their light elemental composition and ordered framework structure, COFs have the characteristics of low density, rich pore configuration and high specific surface area, making them an up-and-coming material for energy storage applications. 18–22 Since Professor Yaghi synthesized the first case of crystalline organic porous material connected by borate bond and named it COFs by using the principle of dynamic chemistry in 2005, hundreds of cases of such materials have been reported after more than a decade of development.…”