In Situ Synthesis of Vacancy-Rich Titanium Sulfide Confined in a Hollow Carbon Nanocage as an Efficient Sulfur Host for Lithium–Sulfur Batteries
journal contributionposted on 2021-08-30, 15:34 authored by Yiming Zhang, Yubing Si, Wei Guo, Xiang Li, Shuai Tang, Zhaoxin Zhang, Xin Wang, Yongzhu Fu
The practical application of lithium–sulfur batteries (LSBs) is partially impeded by large volume variation, severe shuttle effect, and inferior electrical conductivity of sulfur. On this account, a template-free arc-discharge method for the synthesis of TiSx (1.5 < x < 2)@HCN (hollow carbon nanocage) as an efficient sulfur host is developed for LSBs. TiSx@HCN can accommodate the volume changes of active materials and inhibit the shuttle effect of lithium polysulfides (LiPSs). Theoretical calculation shows that the defective titanium sulfide accelerates the conversion of long-chain LiPSs to intermediate species and promotes the redox reactions. As a consequence, the resulting hybrid cathode composited with sulfur exhibits excellent electrochemical performances. A reversible capacity of 1118.6 mA h g–1 is obtained under 0.1 C with a slow capacity decay of 0.108% per cycle for 200 cycles. The synthetic strategy provides a facile platform for the synthesis of nanocomposite materials.
Read the peer-reviewed publication
theoretical calculation showssynthetic strategy providesinferior electrical conductivityhollow carbon nanocage2 )@ hcnslow capacity decaylarge volume variationsevere shuttle effectefficient sulfur hostshuttle effectvolume changesreversible capacityx </sub ><situ </redox reactionspractical applicationper cyclepartially impedednanocomposite materialslithium polysulfideslipss ).intermediate speciesh gfree arcfacile platformdischarge methodchain lipssactive materials></ sub200 cycles