In Situ Built Nanoconfined TiO_2 Particles in Robust-Flexible Mxene@Rgo Conductive Framework Enabling High-Performance Hybrid Magnesium–Sulfur Batteries

摘要

The exploration of new and efficient sulfur cathodes through nanostructuredmaterials design is vital for the development of high-performancemetal–sulfur batteries, which is a promising candidate for next-generationenergy storage systems. However, the shuttle behavior and sluggish reactionkinetics of polysulfides hinder the application of sulfur cathodes. Herein, a 3DMXene/reduced graphene oxide (rGO) composite conductive framework withsuperior specific surface area, structural stability, and ionic/electronicconductivity is constructed. On this basis, the TiO_2 nanoparticles, in situgrown in the interlayer between MXene and rGO can be used as adsorptiveand catalytic active site for polysulfides to accelerate the electrochemicalreaction kinetics and alleviate the shuttle effect, thereby improving cyclestability. Consequently, the sulfur-loaded MXene-TiO_2@rGO compositeelectrodes present a high reversible capacity of 1052.0 mAh g~(?1) at 0.2 C after200 cycles, favorable high-rate capability, and splendid long-termperformance, retaining 445.6 mAh g~(?1) capacity after 1000 cycles at 2 C inhybrid Mg/Li–S batteries. This work provides a new insight for using MXeneas the sulfur host with high performance for metal–sulfur batteries.