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Metal-organic-frameworks-derived nanostructures have received broad attention for secondary batteries. However, many strategies focus on the preparation of dispersive materials, which need complicated steps and some additives for making electrodes of batteries. Here, we develop a novel free-standing Co9S8 polyhedron array derived from ZIF-67, which grows on a three-dimensional carbon cloth for lithiumâ€"sulfur (Liâ€"S) battery. The polar Co9S8 provides strong chemical binding to immobilize polysulfides, which enables efficiently suppressing of the shuttle effect. The free-standing S@Co9S8 polyhedron array-based cathode exhibits ultrahigh capacity of 1079 mAh gâˆ'1 after cycling 100 times at 0.1 C, and long cycling life of 500 cycles at 1 C, recoverable rate-performance and good temperature tolerance. Furthermore, the adsorption energies towards polysulfides are investigated by using density functional theory calculations, which display a strong binding with polysulfides. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel magnetic nanoparticles-assembled composite is presented for Li-S battery. • One-dimensional chain-like structure accommodates volumetric change. • Magnetic composite suppresses the shuttle effect of polysulfides. • Repeatable rate-performance is achieved. Lithium-sulfur battery is of great interest because of high theoretical energy–density and low cost. While the large volumetric change of sulfur and shuttle effect restrict its development. Here, we develop a one-dimensional chain-like Fe 3 O 4 prepared through the self-assembly of magnetic particles as sulfur host. The Fe 3 O 4 @S cathode shows a capacity 457 mAh g−1 after 150 cycles, and a 99% Coulombic efficiency. In addition, rate-performance after three rounds delivers stable capacities after repeated measurements. The electrochemical performance is ascribed to the one-dimensional nano-chain structure provides fast pathways for electron transportation, and accommodates volumetric change of sulfur in charge–discharge. Those findings provide a potential strategy to develop high-performance nanocomposite for secondary batteries. [ABSTRACT FROM AUTHOR]

Current lithium‑sulfur (Li S) batteries have some severe issues such as shuttle effect of polysulfides and volumetric expansion of sulfur, even though their high theoretical energy density is attractive. Herein, we present a porous multi-walled ZnCo 2 O 4 sphere prepared by a self-reduction approach as sulfur host for Li S battery cathode. During the annealing of an inorganic-organic hybrid precursor, ZnCo 2 O 4 spheres are partially reduced by the released carbon monoxide, resulting in the formation of ZnO and CoO nanoparticles which are subsequently etched by acid, finally forming mesopores throughout the multi-walled ZnCo 2 O 4 spheres. The multi-walled ZnCo 2 O 4 provides sufficient space for accommodating the volumetric change of sulfur. The adsorption measurements show that the multi-walled ZnCo 2 O 4 can adsorb the polysulfides efficiently, which suppresses the shuttle effect. After cycling 1000 times at a rate of 0.5C, the multi-walled ZnCo 2 O 4 @S composite remains a capacity of 590 mAh g−1. The rate-performance is well recoverable during repeated tests. Moreover, the capacities at relatively low and high temperatures of − 5 and 50 °C are 654 and 619 mAh g−1 after 100 cycles, respectively, indicating a potential for applications Unlabelled Image • A novel multi-walled ZnCo 2 O 4 @S composite is presented for lithium-sulfur battery. • Porous multi-walled structure suppresses the shuttle effect of polysulfides. • Multi-walled ZnCo 2 O 4 @S cathode exhibits a long cycling life of 1000 cycles. • Stable rate-performance and capacities at low and high temperatures are achievable. [ABSTRACT FROM AUTHOR]

Huge volume-change of sulfur and the shuttle effect of polysulfides during charge-discharge severely restrict the electrochemical performance of lithium-sulfur (Li-S) batteries. Herein, we present a novel three-dimensional (3D) multi-layered and porous CuS scaffold derived from metal organic foams (MOFs) as high-performance sulfur host for Li-S batteries. The CuS/S composites enable an optimal environment for accommodating the volume-change of sulfur, and the multiple CuS layers form several shields to prevent the loss of sulfur and polysulfides, efficiently suppressing the shuttle effect. The batteries based on the CuS/S composites exhibit a stable capacity of 750 mAh g−1 after 200 cycles at 0.1 C, and a well-recoverable rate-performance after being tested for three rounds repeatedly. Furthermore, density functional theory (DFT) calculations confirm the novel sulfur host exhibits a strong adsorption ability to polysulfides with large adsorption energies and charge transfers towards Li 2 S 4 , Li 2 S 6 , and Li 2 S 8. Image, graphical abstract [ABSTRACT FROM AUTHOR]