Layered structure Ti₃C₂ MXene as a functional catalyst for advanced electrochemical performance

Abstract

The shuttle effect and slow reaction kinetic of polysulfide mainly lead to poor electrochemical performance and hinder the practical application of Li–S batteries. Herein, mesoporous Ti₃C₂ MXene (MTC) is successfully prepared and designed as sulfur host materials in Li–S batteries. Benefiting from the high electrical conductivity, mesoporous structure, and strong interaction with polysulfide, MTC could accelerate the redox reaction kinetics of polysulfide. Therefore, the as-prepared MTC host could act as an efficient polysulfide immobilizer to inhibit the shuttle effect. At the same time, the MTC also could serve as a catalyst to promote polysulfide conversion. As a result, the as-prepared MTC/S composites maintain the high capacity of 689 mAh g⁻¹ at 1 C after 500 cycles, demonstrating excellent cycling stability. This work provides promising cathode materials for future practical applications of Li–S batteries.