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'.