Unveiling\nthe Dual Potential of the MoS<sub>2</sub>@VS<sub>2</sub> Nanocomposite\nas an Efficient Electrocatalyst for\nHydrogen and Oxygen Evolution Reactions

Clean and reliable energy sources\nare essential amidst growing\nenvironmental concerns and impending energy shortages. Creating efficient\nand affordable catalysts for water splitting is a challenging yet\nviable option for renewable energy storage. Traditional platinum-based\ncatalysts, while highly active, are quite expensive. Our study introduces\ntwo-dimensional (2D) MoS<sub>2</sub>@VS<sub>2</sub> nanocomposites,\ndeveloped using hydrothermal technique, as a bifunctional catalyst\nfor the electrolysis of water into valuable products. Structural studies\nrevealed the formation of MoS<sub>2</sub>@VS<sub>2</sub> nanocomposites\nwith a nanoflake-like structure, where MoS<sub>2</sub> nanosheets\ngrow on the VS<sub>2</sub> surface. This 2D-based electrocatalyst\ndemonstrated exceptional reaction kinetics, with low overpotentials\nof 265 mV for the hydrogen evolution reaction (HER) and 300 mV for\nthe oxygen evolution reaction (OER) at 10 mA/cm<sup>2</sup>. Furthermore,\nthe electrocatalyst displayed small Tafel slopes of 65 mV/dec and\n103 mV/dec for HER and OER, respectively, along with excellent stability.\nThe unprecedented catalytic activity stems from the synergistic effect\nbetween semiconducting MoS<sub>2</sub> and metallic VS<sub>2</sub>. Density functional theory calculations confirmed that this synergy\nenhances the electrical conductivity, facilitating efficient electron\ntransfer during the reaction and providing an abundance of exposed\nactive sites. These results mold MoS<sub>2</sub>@VS<sub>2</sub> nanocomposites\nas promising electrocatalysts for overall water splitting, paving\nthe way for sustainable energy future.