Details

Autor(en) / Beteiligte

• Xu, Da
• Ma, Kun
• Chen, Ling
• Hu, Yanjie
• Jiang, Hao
• Li, Chunzhong

Titel

MXene interlayer anchored Fe3O4 nanocrystals for ultrafast Li-ion batteries

Ist Teil von

• Chemical engineering science, 2020-02, Vol.212, p.115342, Article 115342

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2020

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• •The Fe3O4 nanocrystals are well-distributed between Ti3C2 interlayers.•The 2D confinement effects stabilize the hybrids with high exposure of active sites.•The Fe3O4@Ti3C2 hybrids possess a rapid and stable charge/discharge capability. Balancing energy density and charging rate has been identified as a great challenge for Li-ion batteries (LIBs), which mainly hinges on developing high-performance electrode materials. Herein, we have developed novel Fe3O4@Ti3C2 hybrids, in which the Fe3O4 nanocrystals are well-anchored between Ti3C2 interlayers with the assistance of the synergistic effects of 2D physical confinement and TiOFe covalent bonds. Such structural design can address the dispersion and volume change of nanocrystals during continuous charge/discharge with the enhancement of structural stability and the exposure of abundant active sites for each component. Meantime, the charge polarization caused by the TiOFe covalent bonds greatly accelerates the lithiation reaction kinetics and electrons transfer. These advantages endow the Fe3O4@Ti3C2 hybrids with a very high specific capacity of 1172 mAh g−1 and a rapid charging capability of 366 mAh g−1 in 66 s. A 90% capacity retention can be maintained even through 1000 cycles at 5 A g−1. More impressively, we can also achieve a free-standing electrode by a simple vacuum filtering, exhibiting a high areal capacity of 4.2 mAh cm−2 at 4.4 mg cm−2 almost without sacrificing gravimetric capacity. The present 2D confined strategy provides a new notion to construct satisfactory electrodes for energy storage.