CoMoO4 nanorods coated separator for high-performance lithium sulfur batteries

Since the separator commonly used in lithium sulfur batteries has a large pore size and the adsorption effect of polyolefin based materials on soluble polysulfides is not obvious, the research on the modification of separator has aroused great interest. In this paper, the effects of different sizes of CoMoO4 nanorods as functional coating materials on the performance of lithium-sulfur batteries were investigated. The results prove that there is a strong affinity between the Co-O-Mo polar bond of CoMoO4 and LiPSs, which can enhance the chemisorption of LiPSs; Moreover, compared with CoMoO4-12, CoMoO4-24 nanorods with smaller particle size can increase the contact area and reactive sites with electrolyte, and the electrolyte penetration is promoted in the CoMoO4-24 coated separator, and the rapid transformation of LiPSs during charge and discharge is realized. Therefore, the Li-S battery assembled with CoMoO4-24 coated separator can deliver an initial capacity of 1018.5 mAh g−1 at 0.2C and a capacity retention of 745.5 mAh g−1 after 200 cycles, higher than the cells assembled with CoMoO4-12 coated separator and blank separator, exhibiting more remarkable electrochemical performance.