MXenes are emerging 2D materials that have demonstrated excellent combined metallic electrical conductivity and hydrophilicity. They have been extensively studied in applications like energy storage, catalysis, optoelectronics, and so on. In this work, the carbon sourced from carbon soot extracted from fossil fuel combustion wastes was used to produce Ti3C2Tx MXene for the first time. The recyclable carbon-derived MXene/iron oxide (Fe3O4) composites with different concentrations of Fe3O4 were synthesized via a hydrothermal route. The successful synthesis of the MXene/Fe3O4 composites was confirmed by the SEM, HRTEM, EDX, UV–Vis, XRD, FTIR, and XPS analyses. Electron images morphologically revealed the existence of Fe3O4 within the as-synthesized composites, while UV–Vis spectra detected the surface plasmon resonance peaks of MXene and Fe3O4, respectively. The XRD spectra identified the crystalline structure of MXene at 5.7° (002) and 25.3° (006), as well as the magnetite Fe3O4 at 18.2° (111) and 38.2° (311), which aligned well with the presence of Ti-O and Fe-O bands observed in the FTIR data. The XPS study also confirmed the presence of the Fe element within the composites. The electrochemical performance of composite as electrode material towards the cathode VO2+/VO2+ redox reaction was investigated. The synergistic effect of both MXene and metal oxide improved the electrode kinetic activity towards the redox reaction, as evidenced by the voltage peak separation (ΔE) and the ratio of peak currents (IO/IR) values determined in cyclic voltammetry (CV), and the charge transfer process probed by electrochemical impedance spectroscopy (EIS). The specific capacity of the battery with the composites was increased along with the improvement of retention strength. The MXene/Fe3O4 5 wt% composite displayed the highest electrochemical catalytic activity with the lowest ΔE (124 mV), IO/IR of about 1, producing specific capacities of 10.2 Ah L-1 and energy efficiency of 70.1 %. The nature of MXene and Fe3O4, morphological features, and higher surface area of composites increased the kinetic activity of the electrode, enabling the composites to be potentially applied in the vanadium redox flow battery (VRFB) system.