Application of carbon nanotubes doped with zif-67 derived nickel‑cobalt‑manganese selenide in cathode materials of lithium‑sulfur batteries

Abstract

Given the rising need for energy storage systems with high energy density and extended durability, lithium‑sulfur batteries have garnered interest due to their elevated theoretical specific capacity and energy density. However, the practical application of lithium‑sulfur (LiS) batteries faces several obstacles, including the low conductivity of sulfur and the dissolution of lithium polysulphides during cycling, leading to low cycling stability and capacity degradation. In this study, which is dedicated to solving the problems of poor conductivity and dissolution of polysulfides faced by lithium‑sulfur (LiS) batteries in practical applications, NiCoMnSe electrode materials were successfully synthesised by employing ZIF-67 as a template and optimised by the addition of carbon nanotubes (CNT). The unique structure and excellent performance of the NiCoMnSe-CNT-2 composites were verified by various characterisation means. The experimental results show that the initial charge-discharge capacity of NiCoMnSe-CNT-2 composite is as high as 1387.3 mAh/g at a current density of 0.2C. After 200 charge-discharge cycles, the specific capacity of NiCoMnSe-CNT-2 composite can still remain at 1084.86 mAh/g. The study therefore makes an important contribution to progress in the field of clean energy storage.