A facile in‒situ synthesis of ZIF‑8 nanoparticles anchored on reduced graphene oxide as a sulfur host for Li‑S batteries

Abstract Because of the severe “shuttle effect” and poor conductivity of polysulfides for lithium‒sulfur batteries, some sulfur hosts as cathodes exhibit unsatisfying electrochemical performances. In this work, ZIF‑8 nanocrystals attached on reduced graphene oxide (ZIF‑8@rGO) was prepared through a hydrothermal process and subsequent in‑situ conversion reaction. When served as sulfur host for lithium‒sulfur batteries, the ZIF‑8@rGO/S nanocomposite delivered a discharge capacity of 523 mAh g‒1 for 0.2 A g‒1 over 200 cycles along with a high Coulombic efficiency, exhibiting an improved long‒term cycle stability. Such an improved cycle stability is related to the unique merits of ZIF‑8@rGO/S nanocomposite, including tight combination, excellent conductivity, abundant reactive sites and adequate specific surface area. Consequently, the in‑situ conversion reaction strategy could be also used to construct many other graphene‒based nanocomposites as sulfur hosts to enhance their electrochemical performances in lithium‒sulfur batteries.