A Sustainable Route to Ruthenium Phosphide (RuP)/Ru Heterostructures with Electron‐Shuttling of Interfacial Ru for Efficient Hydrogen Evolution

Abstract Ruthenium (Ru) is a promising electrocatalyst for the hydrogen evolution reaction (HER), despite suffering from low activity in non‐acidic conditions due to the high kinetic energy barrier of H 2 O dissociation. Herein, the synthesis of carbon nanosheet‐supported RuP/Ru heterostructures (RuP/Ru@CNS) from a natural polysaccharide is reported and demonstrates its behavior as an effective HER electrocatalyst in non‐acidic conditions. The RuP/Ru@CNS exhibits low overpotential (106 mV at 200 mA·cm −2 ) in alkaline electrolyte, exceeding most reported Ru‐based electrocatalysts. The electron shuttling between Ru atoms at the RuP/Ru interface results in a lowered energy barrier for H 2 O dissociation by electron‐deficient Ru atoms in the pure Ru phase, as well as optimized H * adsorption of electron‐gaining Ru atoms in the neighboring RuP. A low H * spillover energy barrier between Ru atoms at the RuP/Ru interface further boosts HER kinetics. This study demonstrates a sustainable method for the fabrication of efficient Ru‐based electrocatalysts and provides a more detailed understanding of interface effects in HER catalysis.