A reverse-design-strategy for C@Li3VO4 nanoflakes toward superb high-rate Li-ion storage

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2021-01, Vol.9 (32), p.17270-17280
• Main Authors: Xu, Jie, Liang, Pei, Zhang, Dongmei, Cunyuan Pei, Zhang, Zongping, Yang, Shuyue, Ni, Shibing
• Format: Article
• Language: eng ; jpn
• Subjects: Anodes; Design; Discharge; Discharge capacity; Electrode materials; Etching; Interfaces; Ion storage; Lithium ions; Reaction kinetics
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d1ta05662j

While the design of a Li3VO4 (LVO) anode is severely hindered by its hydrophilicity, here the state-of-the-art Li3VO4/C nanoflakes with specific crystalline plane exposure (C@LVO-NFs) are designed and synthesized for the first time via a reverse water-etching strategy. A new interfacial Li-ion storage mechanism is demonstrated via theoretical calculations, which is responsible for the ultra-high capacity of the C@LVO-NFs beyond the theoretical value of LVO (850.8 mA h g−1 at 0.2 A g−1 over 150 cycles). Moreover, the exposed crystal planes of LVO and the interfaces with C are proven to be highly conductive for both Li-ions and electrons, giving rise to superior reaction kinetics. These, together, trigger outstanding high-rate and long-life performance of C@LVO-NFs, which outperform most of the LVO-based anode materials. When cycling at a discharge current of 4.0 A g−1 over 6000 cycles, the C@LVO-NFs could deliver a discharge capacity of 637.7 mA h g−1. The reverse strategy for the synthesis of C@LVO-NFs may be referential for the design of advanced LVO-based electrodes, and the outstanding high-rate performance of the C@LVO-NFs demonstrates great potential toward practical applications.