Orchestrating\na Supercapacitive Symphony: Copper–Metal\nOrganic Framework Integrated MXene Nanosheets on Graphite Sheet Electrodes\nUnveiling Its Synergistic Interactions by Density Functional Theory\nStudy

This study reports the successful\nsynthesis of a Cu-based metal–organic\nframework (Cu MOF) integrated with delaminated titanium carbide MXene\n(D-MXene) to form a composite electrode material (Cu MOF/D-MXene)\nfor high-performance supercapacitors at the graphite sheet (GS) electrode.\nThe Cu MOF/D-MXene composite was fabricated using a simple solution-based\napproach and exhibited a remarkably high surface area of 933 m<sup>2</sup> g<sup>–1</sup>. This exceptional surface area and\nthe synergistic interaction between the Cu MOF and D-MXene resulted\nin an outstanding electrochemical performance. The Cu MOF/D-MXene\nelectrode delivered a specific capacitance of 3249.92 F g<sup>–</sup><sup>1</sup> at a current density of 1 A g<sup>–</sup><sup>1</sup> in a three-electrode system with a 6 M KOH electrolyte. Density\nfunctional theory calculations supported the strong interfacial interaction\nbetween Cu MOF and D-MXene, with a calculated binding energy of −9.56\neV. Furthermore, an asymmetric supercapacitor device was constructed\nby using Cu MOF/D-MXene as the cathode and activated carbon as the\nanode. This device achieved a specific capacitance of 746.53 F g<sup>–</sup><sup>1</sup> at 1 A g<sup>–</sup><sup>1</sup> within a potential window of 1.5 V. Moreover, this study demonstrates\nexcellent stability, retaining 95% of its initial capacitance after\n10,000 cycles at a high current density of 15 A g<sup>–</sup><sup>1</sup>. These findings highlight the potential of Cu MOF/D-MXene\ncomposites as promising electrode materials for next-generation supercapacitors\nwith exceptional energy storage capabilities and long-term cycling\nstability.