MXene/f-MWCNT Nanocomposite Film: A Spray-deposited scalable fabrication for flexible electrochemical device

The growing demand for flexible and wearable electronics has accelerated research into lightweight, flexible and efficient energy storage systems such as solid-state supercapacitors. However, achieving high electrochemical performance in flexible configurations remains a key challenge due to limitations in electrode materials and mechanical integrity. In this work, we report the fabrication and evaluation of flexible supercapacitors based on Ti ₃ C ₂ /f-MWCNT composite electrodes deposited onto Kapton substrates via spray pyrolysis technique. Functionalized multi-walled carbon nanotubes (f-MWCNTs) were incorporated into Ti ₃ C ₂ MXene in varying weight ratios (2 to 8 wt. %) to optimize conductivity and structural stability. The Ti ₃ C ₂ /f-MWCNT (92%:8%) composition demonstrates a moderate but stable areal capacitance of ~ 371.85 µF.cm ^− 2 at 10 mV/s suitable for ultra-thin flexible film applications on Kapton substrates with low charge transfer resistance (Rct) and stable capacitive response over a wide scan rate range. Long term cycling tests showed ~ 85% capacity retention after 1000 charge discharge cycles. These results highlight the Ti ₃ C ₂ /f-MWCNT (92%:8%) hybrid as a promising electrode material for next-generation flexible, compact, low-power and solid-state energy storage applications.