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We demonstrated the efficient coupling of BiFeO3 (BFO) ferroelectric material within the carbon–sulfur (C-S) composite cathode, where polysulfides are trapped in BFO mesh, reducing the polysulfide shuttle impact, and thus resulting in an improved cyclic performance and an increase in capacity in Li-S batteries. Here, the built-in internal field due to BFO enhances polysulfide trapping. The observation of a difference in the diffusion behavior of polysulfides in BFO-coupled composites suggests more efficient trapping in BFO-modified C-S electrodes compared to pristine C-S composite cathodes. The X-ray diffraction results of BFO–C-S composite cathodes show an orthorhombic structure, while Raman spectra substantiate efficient coupling of BFO in C-S composites, in agreement with SEM images, showing the interconnected network of submicron-size sulfur composites. Two plateaus were observed at 1.75 V and 2.1 V in the charge/discharge characteristics of BFO–C-S composite cathodes. The observed capacity of ~1600 mAh g−1 in a 1.5–2.5 V operating window for BFO30-C10-S60 composite cathodes, and the high cyclic stability substantiate the superior performance of the designed cathode materials due to the efficient reduction in the polysulfide shuttle effect in these composite cathodes.
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This content will become publicly available on October 24, 2026
Dopamine Surface Functionalized 1D Titania Lepidocrocite Porous Mesostructured Particles for Improved Polysulfide Anchoring in Lithium Sulfur Cells
Lithium‐sulfur (Li‐S) batteries offer high specific capacities but their development is hindered by several issues, most notably polysulfide shuttle. Previously, a new form of titania nanomaterial, 1D lepidocrocite (1DL) nanofilaments was shown to serve as a sulfur (S) host for Li‐S batteries. In this work, porous mesostructured particles are introduced as a new morphology of the titania 1DL to improve its performance as a S host. Furthermore, employing a facile, aqueous, one‐step surface functionalization with dopamine enhances 1DL interactions with S, as confirmed by changes in infrared spectroscopy peaks and an increase in d‐spacing via X‐ray diffraction. This surface functionalization results in a reduction of 1DL band gap energy (Eg) from 3.62 to ≈2.29 eV, resulting in a 2.6‐fold increase in electrical conductivity. Additionally, the surface functionalization renders a more conformal coating of S on the 1DL, leading to increased S utilization and interaction with the 1DL. Electrochemical testing shows a 20% reduction in the polysulfide shuttle current in comparison to base 1DL and 560 mAh g−1at 0.5 C at a S‐loading of 2 mg cm−2. Postmortem X‐ray photoelectron spectroscopy analysis also reveals stronger thiosulfate signals in the dopamine‐functionalized 1DLs, further confirming improved S interactions compared to untreated 1DL.
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- Award ID(s):
- 2427203
- PAR ID:
- 10649767
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- ChemSusChem
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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