Rational Design of Hierarchical SnO2/1T-MoS2 Nanoarray Electrode for Ultralong-Life Li-S Batteries

The serious shuttle effect of soluble polysulfides inevitably leads to low sulfur utilization and faster capacity decay, thus preventing the development of Li-S batteries. Array electrodes have attracted much attention owing to their binder-free and freestanding features. However, the insufficient surface area, lack of active sites with polysulfides, and poor conductive nature of the array electrode could not satisfy the need for high-rate and long-life Li-S batteries, especially for the high sulfur loading of Li-S batteries. Thus, in this work, we constructed the hierarchical C@SnO2/1T-MoS2 (C@SnO2@TMS) array electrode as the sulfur host. The hierarchical C@SnO2@TMS demonstrated strong adsorption with polysulfides, which could effectively facilitate polysulfide redox kinetics. With the C@SnO2@TMS/S as the electrode, the batteries achieved superb C-rate properties, high specific capacity, and ultralong lifespan. Even undergoing 4000 cycles at 5 C, battery could retain a high specific capacity of 448 mAh g(-1) with the capacity decay as low as 0.009% per cycle.