Controlled nanosheet morphology of titanium carbide Ti3C2Tx MXene via drying methods and its electrochemical analysis

The different temperature drying processes were carried out at −60 °C, 15 °C, and 60 °C to control the nanosheet morphology of MXene matrix. The MXene electrode prepared at −60 °C (denoted as LT-Ti3C2Tx) produced more nanosheet arrays than those with drying temperatures of 15 °C and 60 °C (denoted as RT-Ti3C2Tx and HT-Ti3C2Tx MXene electrodes, respectively). The results of BET and electrochemical measurements show that the specific surface area and capacitance initially decrease and then increase with the change in nanosheet layers in MXene. Among these prepared electrodes, LT-Ti3C2Tx, with a well-controlled nanosheet array, showed outstanding specific capacitance (Cs) of 467.4 F g−1 at current density of 0.5 A g−1, and 98.13% stability after 5000 cycles. Furthermore, an LT-Ti3C2Tx // LT-Ti3C2Tx symmetric supercapacitor device (SSD) was assembled, employing the LT-Ti3C2Tx with a well-controlled nanosheet acting as both anode and cathode. The SSD exhibited high energy density of 5.67 Wh kg−1 at power density of 589.09 W kg−1, and long cycle life electrochemical stability of 99.9% after 5000 cycles. These promising results show that MXene electrodes prepared by low-temperature drying (i.e. –60 °C) may be useful for supercapacitor applications.