Redox-assisted construction of Nano-Ag driven MXene-based flexible electrode for excellent cycling stability

MXene shows great potential in the field of flexible electrodes owing to its distinctive two-dimensional structure, high conductivity, and large specific surface area. Nonetheless, during repeated bending, the bonding between the electrode and the conductive substrate weakens, which leads to a decrease in conductivity and, ultimately, a decline in the cycling stability of flexible devices, limiting their practical applications. Based on this, this paper presents the preparation of a MXene-Ag composite with excellent flexibility and cycling stability through a simple redox reaction. Electrochemical performance tests reveal that the material achieves a high specific capacitance of 191 F g −1 at a current density of 1 A g −1 and demonstrates an impressive capacity retention of 95.8 % after 10000 cycles at 5 A g −1 . To further assess the electrochemical performance under bending conditions, MXene-Ag//AC flexible asymmetric solid-state supercapacitors are assembled. Surprisingly, after 1250 charge/discharge cycles at bending angles of 30°, 60°, and 90°, the device still maintains a capacitance retention of 97.2 % (5 A g −1 ), which is a 7 % increase compared to before Ag loading. This demonstrates that the addition of Ag contributes to the improved electrochemical cycling stability of the flexible device.