Waxberry-Shaped Ordered Mesoporous P-TiO2−x Microspheres as High-Performance Cathodes for Lithium–Sulfur Batteries

Abstract

As a candidate for a new generation of inexpensive and high-performance energy storage systems, lithium–sulfur (Li–S) batteries have attracted widespread research. However, the development and application of Li–S batteries are limited by severe polysulfide dissolution and slow reaction kinetics. Herein, a type of ordered mesoporous P-TiO2−x microsphere with a waxberry-like shape as the sulfur host material for Li–S batteries is put forward, which combines the radially arranged mesoporous structure with oxygen defects in the mesoporous framework. In addition, the introduction of phosphorus impurities greatly improves the conductivity of the sulfur electrode, enhances electron mobility, and promotes the interaction between the sulfur species and P-TiO2−x microspheres. Finally, S/P-TiO2−x cathodes have achieved a high capacity of 1174.9 mAh g−1 at 0.2C and stable cycling (the average capacity attenuation is only 0.086% per cycle at 1C after 600 cycles).