Two-dimensional (2D) transition metal carbide and nitride nanomaterials, known as MXenes, have attracted broad attention due to their high electrical conductivity, pseudocapacitance, and mechanical flexibility, making them ideal for wearable energy storage systems. Among these, Ti₃C₂Tₓ MXenes stand out for their excellent electrochemical properties and easy processability in aqueous media. In this study, Ti₃C₂Tₓ nanosheets were synthesized using an optimized, minimally intensive layer delamination (MILD) etching process with two Ti₃AlC₂ MAX phase precursors of 40 μm and 100 μm. The influence of precursor size on the structure, morphology, and electrochemical behavior of MXenes was systematically investigated. Characterization by X-ray diffraction (XRD), zeta potential, dynamic light scattering (DLS), and scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) confirmed the formation of well-delaminated nanosheets with enhanced lateral dimensions. The improved electrical conductivity of MXene films prepared from larger flakes was confirmed by four-point probe measurements, showing superior charge transport compared to films from smaller precursors. The MXene dispersions were applied onto a cotton substrate via dip-coating, producing flexible and conductive textile electrodes. Electrochemical measurements, including cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD), revealed that electrodes from larger Ti₃C₂Tₓ nanosheets exhibited higher specific capacitance than those coated with smaller flakes. The results demonstrate that increasing the lateral size of Ti₃C₂Tₓ MXene enhances electron transport, improving the electrochemical performance of flexible MXene/cotton-based electrodes. When assembled into a flexible solid-state supercapacitor with an H₂SO₄/PVA gel electrolyte, the device operated reliably and powered a small light-emitting diode. These findings provide insights into designing nanostructured MXenes for next-generation wearable supercapacitors and nanoelectronic devices.

Acknowledgements: The authors acknowledge the financial support of the Slovenian Research and Innovation Agency (ARIS) through Research Project No. J2-50087 and the research core program group Textile Chemistry and Advanced Textile Materials No. P2-0118 within the Young Researchers Programme.