Efficient Hydrogen and Oxygen Evolution Reactions by Using the V₂CTx@Sm Nanocomposite

The rational design and advancement of highly efficient and readily available bifunctional electrocatalysts are crucial in pursuing renewable-energy-driven electrocatalytic water splitting as a potential strategy for clean hydrogen generation. Researchers have increasingly focused on transition-metal carbides (MXenes) in the past decade due to their distinctive properties, particularly their potential as cocatalysts in electrocatalytic systems. Herein, we have presented a method for surface modification of V2CTx MXene to create an efficient bifunctional electrocatalyst for water-splitting applications. The desired results are achieved through the intercalation of rare earth element Sm (samarium) with V2CTx MXene by the sonochemical method. The anchoring of samarium on the surface of two-dimensional MXene served as a conductive medium, and their extensive interfacial effects enabled the fast transportation of ions by creating short and conductive channels at the electrode–electrolyte interface by exposing more active sites. The OER and HER electrocatalytic activity of the electrode material was investigated by using a 1.0 M KOH electrolyte. The results showed that the Sm@V2CTx nanocomposite (referred to as V1) exhibited exceptional performance for the OER with an overpotential of 350 mV (vs RHE) delivered at a current density of 10 mA cm–2 and a Tafel slope of 100 mV/dec. For HER, the system is capable of delivering an overpotential of 236 mV (vs RHE) and fast kinetics, having a Tafel slope of 88 mV/dec. Furthermore, it exhibits excellent stability for over 14 h. This research showcases the capability of earth-abundant MXene materials and the modification of their electrocatalytic activity to act as a foundation for creating a broad range of high-performance, environmentally sustainable, and cost-effective electrocatalysts.