Synthesis of hierarchical structure MXene/PANI composite hybrid electrodes for supercapacitors

An MXene (Ti3C2Tx)/polyaniline (PANI) composite was successfully synthesized by the etching of Ti3AlC2 MAX and a simple polymerization process. In the obtained MXene/PANI composite, a dense covering of PANI appears on the surface and interlayers of two-dimensional MXene owing to electrostatic interaction. The electrochemical properties of Ti3C2Tx MXene, PANI, and MXene/PANI composite electrodes were investigated. The crystal phase data and morphology of the samples were observed by X-ray diffraction analysis, scanning electron microscopy, and transmission electron microscopy. The electrochemical properties of the electrode materials were measured in a three-electrode system using cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. The results demonstrate that the MXene/PANI electrode has a higher specific capacitance of 458.3 Fg−1 at a scan rate of 5 mVs−1 compared to the pure Ti3C2Tx MXene and PANI electrodes and a capacitance retention of 95.5 % after 1000 cycles at a current density of 5 Ag−1, indicating that MXene/PANI can be regarded as a promising electrode material for supercapacitors.