Boosting Hydrogen Evolution in Neutral Medium by Accelerating Water Dissociation with Ru Clusters Loaded on Mo2CTx MXene

Electrocatalytic hydrogen evolution reaction (HER) in mild neutral medium is a compelling goal for environmentally sustainable energy conversion, but its development is greatly limited by slow kinetics. Platinum group noble metals exhibit ultra-high HER activities, but their scarcity and performance instability restrict wide application. Herein, taking advantage of excellent catalyst carrier properties of 2D-layered transition metal carbides (MXenes), highly dispersed of Ru clusters anchored on Mo2CTx MXene are demonstrated as a superior HER electrocatalyst, which is prepared by a facile in situ reduction strategy. The as-prepared Ru/Mo2CTx catalyst exhibits a very low overpotential of 73 mV to achieve a current density of -10 mA cm(-2) and Tafel slope of 57 mV dec(-1) in neutral medium, surpassing performance of most previously reported MXene-based catalysts. In addition, Ru/Mo2CTx catalyst also presents superior stability compared to commercial Pt/C. Experimental results and theoretical calculations indicate that the interaction between Ru clusters modulates the electronic structure of active sites and promotes H2O dissociation and hydrogen desorption.