Covalent polyaniline nanoarrays on MXene/cotton textile electrodes with hierarchical porous structures for flexible and deformable supercapacitor applications

Abstract

Designing lightweight, flexible, and wearable sustainable electric-power sources has attracted increasing attention because of the rapid development of portable electronics. Herein, a hierarchical and flexible polyaniline (PANI)@Ti₃C₂T_x MXene-modified cotton (PANI@MXene/cotton) textile electrode was prepared by layer-by-layer deposition treatment. The cotton skeleton endowed good mechanical strength and tailorability to the electrode. Moreover, covering the surface of the cotton textile with a Ti₃C₂T_x layer provided rich sites for PANI deposition and successive conductive pathways for rapid electron transfer. Besides, in situ polymerization of PANI networks can not only effectively enhance the amounts of redox sites accelerating the ion adsorption but also form a stable chemical bond facilitating the electron transfer. Moreover, the constructed hierarchical architectures provided a higher specific surface area and interconnected channels for ion diffusion. Owing to the synergistic effect between the heterogeneous materials, the PANI@MXene/cotton textile electrode presented a high capacitance of 287.61 F g⁻¹ at 1 A g⁻¹ and an excellent rate performance of 95.72 F g⁻¹ at 10 A g⁻¹ in a 1 M H₂SO₄ electrolyte. After assembling the symmetric all-solid-state textile-shaped supercapacitors, the device showed a maximum energy density of 3.47 Wh g⁻¹, stable long-term cycling (96.2% capacitance retention after 2500 cycles) and outstanding deformation endurance. Thus, the as-designed PANI@MXene/cotton textile-based electrode is of great potential for the next-generation multi-functional textile electronics.