Rational design of MXene/Boron Carbon Nitride nanotube composite electrode for supercapacitors with improved electrochemical properties

3D structures obtained using 1D and 2D materials are promising materials in energy storage. Optimizing the interlayer spacing of 2D MXene through flexible conductive materials is an important step in synthesizing 3D composite electrodes. In this study, flexible and conductive MXene/BCN nanotube composite film electrodes were prepared by vacuum filtration using BCN nanotubes in different weight ratios (10 %, 20 %, and 30 %) in mixed and sandwiched structures. The mixed MXene/BCN10 (m-MX/BCN10) composite film electrode structure attained a specific capacitance of 678 F g-1, the highest of all tested electrodes, and exhibited remarkable cycle stability by retaining 95 % of its capacitance even after 10,000 charge/discharge cycles. In the symmetric supercapacitor (SSC), the cell exhibited a specific capacitance of 97 % after 10,000 charge/discharge cycles. Moreover, SSC showed an energy density of 32 Wh kg-1 and a power density of 11.5 kW kg-1. The composite electrodes made of 2D Ti3C2Tx MXene and 1D BCN nanotube materials open up a new avenue for synthesizing promising materials for energy storage in transition metal carbides and 1D nanotubes or nanowires.

Automated summary

Optimizing interlayer spacing of 2D MXene is important for synthesizing 3D composite electrodes for energy storage. In this study, flexible and conductive MXene/BCN nanotube composite film electrodes were prepared, with a specific capacitance of 678 F g-1 and excellent cycle stability. The composite electrodes made of 2D MXene and 1D BCN nanotubes open up a new avenue for energy storage materials.