A novel free-standing metal organic frameworks-derived cobalt sulfide polyhedron array for shuttle effect suppressive...

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 Co₉S₈polyhedron array derived from ZIF-67, which grows on a three-dimensional carbon cloth for lithium-sulfur (Li-S) battery. The polar Co₉S₈provides strong chemical binding to immobilize polysulfides, which enables efficiently suppressing of the shuttle effect. The free-standing S@Co₉S₈polyhedron array-based cathode exhibits ultrahigh capacity of 1079 mAh g^-1after 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.