<scp>NiFe</scp> ‐layered double hydroxide nanosheets grafted onto carbon nanotubes for functional separator of lithium sulfur batteries

Abstract

A rational design of functional separators that include abundant active sites and high electrochemical stability without Li+ ion transport sacrifice is important for inhibiting the shuttle effect of lithium polysulfides (LiPSs) and improving the utilization efficiency of sulfur for high performance lithium sulfur batteries (LSB). Herein, we report a straightforward modification chemistry of separator through an in-situ assembly of two-dimensional nickel-iron layered double hydroxide nanosheets onto the reticular functionalized carbon nanotubes surface (NiFe-LDH@OCNT) with enriched active sites and interconnected conducting channels. As demonstrated by the spectroscopic and electrochemical characterizations, the NiFe-LDH@OCNT composite features strong adsorption ability towards LiPSs and improvement of the LiPSs redox kinetics, thus effectively suppressing the shuttle effect. In this regard, the LSB cells assembled with the NiFe-LDH@OCNT/PP composite separators achieve the excellent reversibility and good cycling stability over 600 cycles with a low capacity decay rate of 0.085% each cycle at 2 C.