Self-assembled FeF3 nanocrystals clusters confined in carbon nanocages for high-performance Li-ion battery cathode

With the revival of lithium metal anodes, there is an urgent need for matching cathodes to form the next generation batteries with high-capacity and low-cost. A porous hierarchical structure containing FeF3 nanocrystals (3-9 nm) capsulated in conductive carbon nanocages (40-110 nm) was fabricated. The morphology and size of the FeF3 nanocrystals were influenced by the existence of carbon nanocage. During the preparation process, the carbon nanocage inhibited the growth of FeF3 crystals. During the dis/charge process, the carbon nanocages not only restricted the complex conversion reaction (Fe3+ reversible arrow Fe2+ reversible arrow Fe) within the confined space, but also functioned as a bridge for the transmission of electrons, thus enhancing the electrochemical performance of the electrode. As a result, the FeF3/C electrode delivered an excellent reversible capacity of 410 mA h g & minus;1 over 120 cycles at 100 mA g & minus;1. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

A FeF3/C electrode with excellent performance was fabricated, demonstrating its potential in lithium metal anodes.