Conductive Few-Layered 1t-Mose2/Mxene as a Highly Efficient Bidirectional Catalyst for Accelerating Redox Kinetics of Polysulfide

Lithium-sulfur batteries (LSBs) have been regarded as a prospective candidate for next-generation late-model energy storage device due to their merits in gravimetric/ volumetric capacity. However, the practical use of lithium-sulfur batteries is still severely limited by the shuttle behavior and extremely slow sulfur redox kinetics. Herein, a dual-functional conductive 1T-MoSe2/MXene bidirectional catalyst as a high-efficiency sulfur host was constructed by few layers 1T-MoSe2 in-situ growth on MXene nano-flakes through one-step solvothermal reaction. Experiments and DFT theoretical analysis reveal that 1T-MoSe2/MXene possess a high electronic conductivity, strong adsorption ability and abundant active sites, which can provide the strong capture and catalytic conversion ability for LiPSs and uniform deposition of Li2S, thus effectively inhibiting the LiPSs shuttle behavior in lithium-sulfur batteries. Benefiting from the enhanced bidirectional sulfur redox kinetics and adsorption capacity, the S/1T-MoSe2/MXene cathode delivers a stable long cycling stability at 0.2 C after 500 cycles, which maintained at 784 mAh g-1 (average capacity fading rate per cycle of 0.07%). Furthermore, a high areal capacity of 6.9 mAh cm-2 was obtained at 0.1 C (after 200 cycles, maintained at 4.9 mAh cm-2 and capacity retention rate is ~73.1%). This work provides a novel way for the development of dual-functional conductive catalyst to accelerate the catalytic conversion of LiPSs