Abstract
? 2022 Elsevier B.V.High-capacity cathode materials of metal fluorides generally undergo low conductivities and sluggish kinetics derived from a multielectron-transfer conversion reaction mechanism, which severely hinder the cycling stability and rate performance towards their commercialization. Herein, a flexible free-standing FeF3/chitosan pyrolytic carbon/reduced graphene oxide (FeF3/C/RGO) film as an additive-free cathode was designed and prepared by a facile hydrothermal strategy followed by sequential freeze-drying, thermal reduction and fluorination post-treatments. The ultrafine FeF3 nanoparticles (NPs, ~30 nm) are confined within highly ordered RGO film, effectively reducing the Li+ diffusion pathway while the RGO sheets act as a matrix to restrict the complicated interlamination reaction (Fe3+?Fe2+?Fe) between adjacent interlayers with the spacing of ~30 nm. Benefiting from the free-standing structure, the FeF3/C/RGO film can achieve an admirable capacity up to 220 mAh g–1 over 200 cycles at 100 mA g–1, showing great potential for wearable and flexible electronic devices.
NSTL
Elsevier