Accelerating Polysulfide Adsorption and Conversion from the Hybrid Phase of TiO2 and N‑Doped Carbon toward High-Performance Li−S Batteries

Abstract

The development of lithium–sulfur (Li–S) batteries is highly dependent on overcoming the technical issues such as the shuttling behavior of lithium polysulfides (LiPSs). In this work, we report a multifunctional layer composed of MXene/ZIF-8 (MXZ) nanohybrids to enhance the electrochemical performance of Li–S batteries. During the preparation of MXZ, ZIF-8 is hybridized with Ti3C2Tx MXene, where the ZIF-8 is decorated on the surface of Ti3C2Tx MXene by in situ growth. During thermal treatment, MXZ developed a hybrid phase of TiO2 (brookite and rutile) as well as N-doped carbon microstructures. Spectroscopic analysis confirms that the complementary contribution by the hybrid phase of TiO2, N-doped carbon microstructures, plays a critical role as electrocatalysts via efficient adsorption and conversion of LiPSs to fulfill high-performance Li–S batteries.