Probe Sonication‐Assisted Synthesis of <scp> Ti ₃ AlC ₂ MAX </scp> Phase and Electrochemical Investigation of Resultant Delaminated <scp> Ti ₃ C ₂ T _x MXene </scp> Nanoflakes for Supercapacitor Applications

ABSTRACT Herein, we report a facile probe sonication‐assisted synthesis of Ti 3 AlC 2 MAX phase and examined the resultant delaminated MXene (d‐Ti 3 C 2 T x ) nanoflakes via tetramethyl ammonium hydroxide for supercapacitor application. The lower shift of (002) basal plane in the X‐ray diffraction pattern of the d–Ti 3 C 2 T x confirms an expansion of the interlayer spacing from 9.16 Å (Ti 3 AlC 2 ) to 14.64 Å (d–Ti 3 C 2 T x ). The flakelike morphology of d–Ti 3 C 2 T x MXene is confirmed through electron microscopic analysis. The X‐ray photoelectron spectroscopic analysis confirms the chemical composition and the surface active termination groups. The d–Ti 3 C 2 T x MXene exhibits a specific capacitance of 255 F g −1 at a specific current of 0.5 A g −1 in an aqueous acidic electrolyte, 1 M H 2 SO 4 . In addition, d–Ti 3 C 2 T x retains 88.6% capacitance and 100% coulombic efficiency over 5000 cycles at 5 A g −1 . Further, a symmetric supercapacitor developed using d–Ti 3 C 2 T x MXene delivers a specific energy of 1.75 Wh kg −1 at a specific power of 194.32 W kg −1 and retains 68.5% capacitance over 5000 cycles.