Ti ₃ C ₂ T _x MXene-Enabled Enhanced Hydrogen Evolution Reaction Activity of MoS ₂

In this work, MoS 2 /Ti 3 C 2 T x MXene heterostructures were synthesized via a one-pot hydrothermal method with varying MXene concentrations to enhance the hydrogen evolution reaction (HER) performance of MoS 2 . Morphological and structural analyses confirm the successful formation of MoS 2 nanoflowers uniformly anchored on MXene surfaces and interlayers. The optimized sample exhibits excellent HER activity with an overpotential of 108 mV at 10 mA cm –2, a Tafel slope of 51.02 mV dec –1, low charge transfer resistance (5.30 Ω), and high double-layer capacitance (107.18 mF cm –2 ). The enhanced performance is attributed to synergistic effects, including the stabilization of the metallic 1T phase of MoS 2 induced by the heterostructure formation, Ti 3 C 2 T x MXene interlayer expansion due to MoS 2 insertion, and efficient MXene-mediated charge transport pathways. Overall, the optimized heterostructure shows a significant reduction in overpotential (∼82%) and increased electrochemically active surface area (∼75%) compared to reported hydrothermally synthesized MoS 2 /MXene systems, demonstrating a highly effective strategy for HER enhancement.