On October 12, the research group led by Prof. Wang Deli published a paper entitled "Hypercrosslinked Polymerization Enabled N-Doped Carbon Confined Fe₂O₃ Facilitating Li Polysulfides Interface Conversion for Li-S Batteries" on Advanced Energy Materials. The first authors are Doctoral students Lu Yun and Qin Jinlei; the corresponding author is Prof. Wang Deli.

Facilitating phase conversion efficiency of Li polysulfides to Li₂S and restraining the dissolution of Li polysulfides are critical for stable lithium-sulfur (Li-S) batteries. Herein, an in situ formed sulfiphilic superfine Fe₂O₃ nanocrystals confined in lithiophilic N-doped microporous carbon (Fe₂O₃/N-MC) is derived from one-step hypercrosslinked polymerization. Uniquely, the dual active sites (Fe₂O₃ and N) in Fe₂O₃/N-MC tend to form "Fe-S, Li-O or Li-N" bonding, and then synchronically enhancing the chemisorption and interface conversion ability of Li polysulfides. As a result, 80 wt% S is loaded on Fe₂O₃/N-MC and the hybrid cathode delivers high mass capacity (730 mA h g^-1) and excellent cycling stability (87.1% capacity retention over 1000 cycles at 5.0 C). Especially, the cathode also exhibits a high reversible areal capacity of 3.69 mA h cm^-2 at a high areal loading (5.1 mg cm^-2) and a lean electrolyte/sulfur (E/S) ratio (7.5 µL mg^-1) over 500 cycles. This work is anticipated to deepen the comprehension of complex Li polysulfides interphase conversion processes and afford new thoughts for designing new host materials.

Link to this paper: https://doi.org/10.1002/aenm.202101780