Structurally oriented black phosphorus/MXene heterostructured fibers for flexible supercapacitors with enhanced ion transport and capacitive charge storage

Abstract

The development of flexible MXene-based fiber supercapacitors (FSCs) with high conductivity and high specific capacitance has become a research hotspot. However, the assembly of nanosheets into macroscopic fibers with regular arrangement and the phenomenon of nanosheet restacking remain a huge challenge, which limits the practical application of flexible MXene-based FSCs. In this paper, a structurally oriented BP/Ti3C2Tx heterostructural fiber was successfully prepared by wet-spinning process, and its ordered channel shortened the ion transport path. black phosphorus (BP) in BP/Ti3C2Tx can not only effectively prevent the restacking of MXene nanosheets, but also greatly improve the mechanical strength (401 MPa) and electrical conductivity (6019 S cm-1), and the pseudocapacitor charge storage capacity of 383.9 F g-1. In addition, the energy density and power density of FSCs assembled with heterostructural fibers can reach 5.1 mWh g-1 and 175 mW g-1, respectively. This work provides a reference for the development of high-performance flexible MXene-based FSCs.