Fabrication of ternary MXene/MnO2/polyaniline nanostructure with good electrochemical performances

The ternary MXene/MnO2/polyaniline (PANI) nanostructure was successfully prepared through a simple, scalable, and reproducible two-step method. First, the interlaced layered MnO2 is grown on the interlayer and surface of MXene through the hydrothermal reaction. And then the composite was covered with conducting polymer PANI through the redox reaction in the ice bath to obtain the ternary MXene/MnO2/PANI nanostructure. The accordion-like MXene substrate has good conductivity and provides electron conduction channels. MnO2 nanosheets not only inhibit the re-stacking of the MXene layer but also form an effective pore space, which is conducive to ion diffusion and transfer. The outer PANI can further improve the electrochemical performance of the composite. The morphology, chemical structure, and crystal phase of the prepared nanostructure were measured in detail by SEM, FTIR, and XRD. In addition, the behavior of the supercapacitor was analyzed through cyclic voltammetry (CV) and galvanostatic charge and discharge (GCD) tests. Test analyses show that the specific capacitance of the MXene/MnO2/PANI nanostructure is about 216 F g−1 at a current density of 1 A g−1. And the capacitance retention rate after 5000 cycles under the two-electrode test system is about 74%.