Abstract
As a promising high-energy chemical power source, lithium-sulfur batteries have attracted extensive attention due to their high theoretical specific capacity (1675 mAh g?1) and high theoretical energy density (2600 Wh kg?1). However, some prominent problems restrict the development of lithium-sulfur batteries, including poor intrinsic conductivity of sulfur, larger volume expansion, and the dissolution of polysulfide. Herein, the porous Zn-Co oxide derived from MOFs (metal-organic framework) coated by highly conductive MXene (ZnCo2O4@Ti3C2) is developed as an efficient sulfur immobilizer for lithium-sulfur batteries (LSBs). Benefitting from the high electronic conductivity of MXene, chemical binding sites of metal oxide for polysulfides, and porous structure for ion transfer, the ZnCo2O4@Ti3C2/S composite demonstrates a balanced high electrochemical performance. A high initial discharge capacity of 1283.9 mAh g?1 with a high initial coulombic efficiency of 98.7% at a low current density of 0.1 C. In addition, this sample exhibits outstanding cycling performance at a high current density of 0.5 C. The results showed that the design strategy of MOFs-derived materials has great potential to promote the development of high-performance LSBs.
NSTL
Elsevier