Flexible Ti3C2Tx MXene/V2O5 composite films for high-performance all-solid supercapacitors. (June 2023)

• Record Type: Journal Article
• Authors: Luo, Wenlong; Sun, Yue; Lin, Zhongtai; Li, Xue; Han, Yongqin; Ding, Jianxu; Li, Tingxi; Hou, Chunping; Ma, Yong
• Is Part Of: Journal of energy storage. Volume 62(2023)
• Publication Date: 2023-06
• Subjects: Ti3C2Tx MXene -- V2O5 nanofibers -- Composite film -- Flexibility -- Supercapacitor; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2023.106807
• Languages: English
• ISSNs: 2352-152X

Abstract

Abstract: Designing and synthesizing flexible self-supporting materials with high electrical conductivity and flexibility are the key to the development of wearable energy storage devices. Herein, a strategy to prepare Ti3 C2 Tx MXene/V2 O5 (MV) films as flexible electrode materials for supercapacitors by vacuum-assisted filtration of a mixture of MXene nanosheets and V2 O5 nanofibers is reported. The introduction of V2 O5 nanofibers effectively suppresses the self-stacking phenomenon of MXene nanosheets, and simultaneously regulates the thickness of the MV films by controlling the amount of V2 O5 nanofibers. Benefiting from the efficient intercalation of V2 O5 nanofibers, the Ti3 C2 Tx MXene/V2 O5 (20 mg) (MV2) film as electrode shows good capacitive performance (319.1 F g ‐1, 0.5 A g ‐1 ) and cycling stability (70.4 %, 5000 cycles, 3 A g ‐1 ). Furthermore, the MV2//MV2 symmetric supercapacitor (SSC) and the MV2//MnO2 asymmetric supercapacitor (ASC) are assembled, which separately have 72.1 % and 83.9 % capacitance retention after 8000 charge/discharge cycles at 2 A g ‐1 . The SSC exhibits an energy density of 18.43 Wh kg ‐1 at 603.2 W kg ‐1 power density, and the ASC provides an energy density of 20.83 Wh kg ‐1 at 374.94 W kg ‐1 power density, indicating their good energy storage capacity. This study provides a new strategy to improve the electrochemical properties and flexibility of Ti3 C2 Tx and a reliable method for its application in flexible wearable devices. Graphical abstract: MXene/V2 O5 film with adjustable thickness is fabricated by suction filtration of MXene nanosheets and V2 O5 nanofibers, and its asymmetric supercapacitor exhibits good flexibility, a capacitance retention rate of 83.9 % after 8000 cycles at 2 A g ‐1, as well as an energy density of 20.83 Wh kg ‐1 at a power density of 374.94 W kg ‐1 . Unlabelled Image Highlights: The flexible MXene/V2 O5 film is fabricated through suction filtration of MXene nanosheets and V2 O5 nanofibers. The introduction of V2 O5 nanofibers can increase MXene layer spacing beneficial to electrolyte ion infiltration. The different devices exhibit a capacitance retention rate of 72.1% and 83.9% after 8000 cycles at 2 A g -1, respectively. The different supercapacitor devices separately exhibit an energy density of 18.43 Wh kg -1 and 20.83 Wh kg -1 .