Mo-Mediated Transition of the Lattice to Long-Range Disorder Enables Ultra-High Current Density Hydrogen Production at Low Potentials

Abstract

High-current hydrogen production at low potential toward hydrogen evolution reaction (HER) is a fatal factor restricting the large-scale production of green hydrogen. Here, a Mo-mediated nickel-based chalcogenides electrocatalyst (U-MoNiS) with long-range disordering through heterogeneous atom-mediated strategies, is proposed. The optimal U-MoNiS is scalable to meet the urgent application needs and it requires an extermely low overpotential (305 mV) to achieve ultra-high current density of 2243 mA cm-2, which is 16.6-fold higher than the noble Pt/C (135 mA cm-2). Strikingly, the U-MoNiS can function well under an ultra-high current up to ~5 A. Operando experiments and calculations reveal the Mo-mediated transition of lattice model to a long-range disordering and regulate the microenvironment of dominant crystal plane, and the surface energy of (110) and (211) drops from 0.180 and 0.165 to 0.077 and 0.100 eV Å-2, respectively. Which exceedingly minimizes the free energy barrier and then accelerates the H* adsorption, and fundamentally contributes to the achievement of efficient hydrogen production at high current density. The proposed strategy to produce hydrogen at ultra-high current would fulfill the dream to create ‘a high effiective catalyst designed as simply as possible'.