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Developing cost-effective and earth-abundant noblemetal-free electrocatalysts is imperative for the imminent electrochemical society. Two-dimensional Ti 3 C 2 T X (MXene) exhibits tunable properties with high electrical conductivity and a large specific surface area, which improve its electrochemical performance. Herein, the lowtemperature annealing method is used to enrich MXene with a maximum number of Ti−O terminals without formation of titanium dioxide (TiO 2 ) under neutral pH conditions. MXene annealed at 200 °C is found to have a large number of Ti−O termination groups, resulting in a large electrochemically active surface area and increased active sites (−O termination groups) and hence excellent electrocatalytic performance compared to other samples as well as previous reported work. The optimized sample is found to show the lowest overpotential value of 0.07 V at 10 mA cm −2 and a Tafel slope of 0.15 V dec −1 toward the hydrogen evolution reaction (HER), whereas for the methanol oxidation reaction (MOR), the current density is 18.08 mA cm −2 , and the onset potential is −0.51 V. In addition, it also shows long-term stability and durability toward HER as well as MOR.

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In the present work, nanohybrids of multi-walled carbon nanotubes (MWCNTs) and nickel sulphide (Ni3S2) have been prepared using hydrothermal method and have been explored as anode material in direct methanol fuel cells (DMFCs). Hydrothermal method has been used to synthesize MWCNTs/Ni3S2 nanohybrids with three different concentrations. These nanohybrids have been characterized through field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller (BET) analysis, X-Ray diffraction (XRD), and Raman spectroscopic techniques. From the electrochemical studies, Cyclic Voltammograms (CVs) and Tafel Plots demonstrate that the MWCNTs/Ni3S2 nanohybrid with optimized Ni3S2 exhibits superior electrocatalytic activity for methanol oxidation reaction (MOR) due to synergistic effects of superior electrocatalytic activity of Ni3S2 and high charge transporting MWCNTs. Moreover the optimized nanohybrid also shows persistent current density over a longer period of time.