Synchronous stabilization of Li–S electrodes by a 1T MoS2@AAO functional interlayer

Abstract

The fast capacity decay and limited cycling life are the two main issues that hinder the practical applications of lithium–sulfur batteries. They are mainly caused by the shuttle effect of polysulfide species and the growth of big lithium dendrites occurring separately on the cathode and anode sides. To simultaneously tackle these problems, we explore a multifunctional interlayer integrating the aligned nanochannel structure of an anodic aluminum oxide (AAO) membrane with porous 1T MoS₂ nanotubes (namely MoS₂@AAO). Benefiting from the high electronic conductivity, sulfiphilic and lithiophilic properties of 1T MoS₂, and the positive surface plus low tortuosity of the straight channels of AAO, the designed interlayer not only guarantees rapid ion/electron transfer and efficacious suppression of the polysulfide shuttle, but also achieves uniform and stable lithium deposition during cycling. Consequently, the MoS₂@AAO interlayer exhibits a high capacity retention of 99.6% at 0.2C after 500 cycles and 90.6% at 1.0C after 1000 cycles. The prototype cathode with a sulfur loading of 5 mg cm⁻² was also investigated, which exhibited over 96% retention of the initial discharge capacity at 0.1C after 50 cycles. This work provides a new solution for simultaneously stabilizing both the lithium anode and sulfur cathode via an integrating approach.