Arbitrary deformable and high-strength electroactive polymer/MXene anti-exfoliative composite films assembled into high performance, flexible all-solid-state supercapacitors. Issue 40 (9th October 2020) - Zhou, Yang
Abstract : As-prepared electroactive polymer/MXene composite films are flexible, anti-exfoliative and exhibit high mechanical strength and the assembled supercapacitors show excellent energy storage performance. Abstract : Flexible all-solid-state supercapacitors (ASSSs) are excellent energy storage devices for portable/wearable electronics, although the development of an excellent comprehensive performance film electrode for the extraordinary flexible ASSSs still faces a great challenge. Here, bendable, foldable and anti-exfoliative Ti3 C2 T x MXene-based films utilized as supercapacitor electrodes are reported. Polyaniline/Ti3 C2 T x composites (i-PANI@Ti3 C2 T x ) were prepared by in situ oxidant-free polymerization of aniline on Ti3 C2 T x nanosheets with p -phenylenediamine (PPD) as an initiator. Lignosulfonate (Lig) and Ti3 C2 T x were constructed into a compact composite (Lig@Ti3 C2 T x ) film based on the hydrogen bonds formed between Lig and Ti3 C2 T x . The Lig@Ti3 C2 T x /i-PANI@Ti3 C2 T x (5/5) hybrid film was produced by vacuum-assisted filtration of the mixed two composite dispersions. The as-prepared films can be arbitrarily deformed (such as bending and folding). They show high tensile strength and vertical-plane (the plane of film) tensile strength with 33.2 and 0.28 MPa for the i-PANI@Ti3 C2 T x film, 75.4 and 0.77 MPa for the Lig@Ti3 C2 T x film, and 53.7 and 0.58 MPa for the Lig@Ti3 C2 T x /i-PANI@Ti3 C2 T x (5/5) film (those of Ti3 C2 T x film are 17.4 and 0.21 MPa), respectively. The enhanced vertical-plane tensile strength of the as-prepared composite films indicates that the large binding force generated between the Ti3 C2 T x nanosheets can effectively prevent the exfoliation of films. The electrodes of the as-prepared i-PANI@Ti3 C2 T x, Lig@Ti3 C2 T x and Lig@Ti3 C2 T x /i-PANI@Ti3 C2 T x (5/5) films assembled into symmetric flexible ASSSs can deliver excellent specific capacitances of 310 F g −1 (∼1001 F cm −3 ), 271 F g −1 (∼881 F cm −3 ) and 295 F g −1 (∼959 F cm −3 ), respectively. In addition, the corresponding supercapacitors exhibit ultrahigh energy densities of 34.8, 30.6 and 33.3 W h L −1, respectively. It is expected that the as-prepared MXene-based films can be applied in various fields, such as electromagnetic-interference shielding and batteries. Furthermore, the as-prepared flexible ASSSs can be practically used as a wearable energy storage device.