MXene-derived titanic acid with an ultralow-potential as a promising anode for aqueous zinc-ion batteries

作者：Hou, Yixin; Chen, Shiyuan; Ma, Pengfei; Mao, Ke; Shi, Junjie; Long, Fei; Su, Jun; Ma, Yanan; Gao, Yihua^*

来源：Journal of Alloys and Compounds, 2023, 938: 168714.

DOI：10.1016/j.jallcom.2023.168714

• MXene derived anode
• Ultralow charging voltage
• RevisableZn2+intercalation
• de-intercalation
• Aqueous zinc-ion battery

Replacing Zn metal with intercalated materials as the aqueous zinc-ion batteries (AZIBs) anode is an ef-fective strategy to solve serious zinc dendrites problem. MXene-based derived materials combine the ad-vantages of both derivatives with excellent electrochemical activity and MXene with high electrical conductivity. Here, we report an in situ derived strategy for synthesizing H2Ti3O7-MXene from common Ti3C2 MXene by one-step hydrothermal process with simultaneous alkalization and oxidation, followed by ion-exchange reaction. It is experimentally verified that H2Ti3O7 -MXene exhibits an extremely low char-ging voltage of only 0.25 V, which has a satisfactory potential for AZIBs anodes. Through characterization analyses, H2Ti3O7-MXene nanoflowers consist of countless connectively interlaced and entangled nanor-ibbons, which shorten the ion diffusion path and accelerate Zn2+ diffusion kinetics. The synergistic effect between H2Ti3O7 and MXene enables H2Ti3O7-MXene to achieve efficient and reversible Zn2+ (de)inter-calation. Specifically, at 0.10 A g-1, the specific capacity of 61.20 mAh g-1 is achieved and no significant discharge specific capacity decline occurs at 0.60-2.00 A g-1. The assembled zinc ion full-cell (ZnxMnO2// H2Ti3O7-MXene) shows the excellent cyclic stability and good coulombic efficiency during 600 GCD cycles. This work proves the feasibility of MXene-based derivatives for AZIBs anode and sheds light on developing efficient intercalated MXene derived anodes.

• 单位
  华中科技大学; 桂林理工大学