Anion-doped CeO2 for high-performance lithium-sulfur batteries

Li-S batteries are potential candidates for next-generation energy storage devices because of their ultra-high theoretical capacity and low cost. However, shuttle effect and slow reaction kinetics hinder further commercialization of Li-S batteries. In the present work, CeO2-xSx was prepared using S-doped CeO2 as a cathode material to address some existing challenges of Li-S batteries. After density function theory calculations, it was found that S doping not only effectively shortens the band gap but also enhances the adsorption capacity of the composite to Li2S6, which has a positive effect on mitigating the shuttle effect. The battery also has a highly reversible cycling capability. The first charge/discharge capacity of the battery at 0.1C reached 1380 mAh/g, while the capacity retention rate of the battery reached 90% after 500 cycles at 1C. This provides a new idea for anion doping to be used to enhance the performance of lithium-sulfur batteries.