Rhenium anchored Ti 3 C 2 T x (MXene) nanosheets for electrocatalytic hydrogen production.

Atomically thin Ti 3 C 2 T x (MXene) nanosheets with rich termination groups, acting as active sites for effective functionalization, are used as an efficient solid support to host rhenium (Re) nanoparticles for the electrocatalytic hydrogen evolution reaction (HER). The newly designed electrocatalyst - Re nanoparticles anchored on Ti 3 C 2 T x MXene nanosheets (Re@Ti 3 C 2 T x ) - exhibited promising catalytic activity with a low overpotential of 298 mV to achieve a current density of 10 mV cm -2 , while displaying excellent stability. In comparison, the pristine Ti 3 C 2 T x MXene requires higher overpotential of 584 mV to obtain the same current density. After being stored under ambient conditions for 30 days, Re@Ti 3 C 2 T x retained 100% of its initial catalytic activity for the HER, while the pristine Ti 3 C 2 T x retained only 74.8% of its initial value. According to our theoretical calculations using density functional theory, dual Re anchored MXene (Re@Ti 3 C 2 T x ) exhibits a near-zero value of Gibbs free energy (Δ G H * = -0.06 eV) for the HER, demonstrating that the presence of Re significantly enhances the electrocatalytic activity of MXene nanosheets. This work introduces a facile strategy to develop an effective electrocatalyst for electrocatalytic hydrogen production.