MoS2 intercalated p-Ti3C2 anode materials with sandwich-like three dimensional conductive networks for lithium-ion batteries

• Published in: Journal of alloys and compounds 2018-02, Vol.735, p.1262-1270
• Main Authors: Zheng, Mei, Guo, Ruisong, Liu, Zhichao, Wang, Baoyu, Meng, Leichao, Li, Fuyun, Li, Tingting, Luo, Yani
• Format: Article
• Language: English
• Subjects: Electrochemical performance; Lithium-ion battery; MoS2; Partially oxidized Ti3C2
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2017.11.250

As a promising anode material, Ti3C2 has got increasing attention in recent years for its brilliant performance in conductivity and hydrophilicity. However, the application of Ti3C2 is limited by its low capacity. Herein, a sandwich-like three dimensional conductive network of MoS2 intercalated p-Ti3C2 (partially oxidized Ti3C2) is fabricated by selective etching and subsequent hydrothermal treatment to overcome the shortcomings of Ti3C2. During the hydrothermal treatment, some TiO2 nanocrystals are formed by partial oxidation of Ti3C2. The ultra high structural stability of TiO2 nanocrystals upon lithium ion insertion and extraction process is beneficial to maintaining the cyclic stability of MoS2 modified p-Ti3C2 composites. In this architecture, MoS2 acts as an intercalation agent to prevent the p-Ti3C2 layers from restacking and facilitate the rapid transportation of electrons and ions between layers. The expanded interlayer space of p-Ti3C2 provides extra free space to alleviate the volume change of MoS2. The optimal content of MoS2 is 20% in this study. The synergistic effect of p-Ti3C2 and 20 wt% MoS2 endows composite with maximum discharge capacity of 656 mAh g−1 at 50 mA g−1, which is significantly higher than the theoretical capacity of Ti3C2 (320 mAh g−1). The sample also shows excellent cycling stability at 500 mAh g−1. Even at high current density of 3000 mAh g−1, a stable specific capacity of 153 mAh g−1 is obtained. These results clearly indicate that intercalation with MoS2 is an effective strategy to improve the electrochemical performance of Ti3C2. [Display omitted] •The MoS2 intercalated p-Ti3C2 anode materials was prepared.•The layer spacing of Ti3C2 was increased after introducing MoS2.•The highest discharge capacities of 656 mAh g−1 was obtained at 50 mA g−1.•Stable cycle performance was gained at 500 mA g−1.•The T20 electrode delivered a capacity of 153.2 mAh g−1 even at 3000 mA g−1.