Intermetallic Fe₂Mo Nanoparticles on Hierarchical Nanoporous Copper for Efficient Hydrogen Evolution Reaction

Developing cost-effective and high-performance non-precious metal-based electrocatalysts for hydrogen evolution reaction is of crucial importance toward sustainable hydrogen energy systems. Herein, we prepare a novel hybrid electrode featuring intermetallic Fe₂Mo nanoparticles anchored on the hierarchical nanoporous copper skeleton as robust hydrogen evolution electrocatalyst by simple and scalable alloying and dealloying methods. By virtue of the highly active intermetallic Fe₂Mo nanoparticles and unique bicontinuous nanoporous copper skeleton facilitating ion/molecule transportation, nanoporous Fe₂Mo/Cu electrode shows excellent hydrogen evolution reaction electrocatalysis, with a low Tafel slope (~71 mV dec⁻¹) to realize ampere-level current density of 1 A cm⁻² at a low overpotential of ~200 mV in 1 M KOH electrolyte. Furthermore, nanoporous Fe₂Mo/Cu electrode exhibits long−term stability exceeding 400 h to maintain ~250 mA cm⁻² at an overpotential of 150 mV. Such outstanding electrocatalytic performance enables the nanoporous Fe₂Mo/Cu electrode to be an attractive hydrogen evolution reaction catalyst for water splitting in the hydrogen economy.