Ultrafine Ruthenium Nanoparticles Anchored on S,N-Codoped Carbon Nanofibers for H₂ and Electricity Coproduction

The development of an energy-saving hydrogen (H2) production system and efficient electrocatalysts is of high importance but challenging. Herein, we report the rational design and synthesis of ultrafine ruthenium (Ru) nanoparticles in situ anchored on S,N-codoped carbon nanofibers (Ru@SNCNFs) by an electrospinning-assisted method. For both the hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR), Ru@SNCNFs demonstrate superior catalytic performances compared to a 20% Pt/C catalyst and most Ru-based catalysts in literatures. When Ru@SNCNFs are applied as bifunctional electrocatalysts, an asymmetric fuel cell is constructed by integrating HER in 0.5 M H2SO4 and HzOR in 1 M KOH and 0.5 M N2H4. Remarkably, it achieves simultaneously H2 and electricity coproduction by further harvesting the electrochemical neutralization energy. Density functional theory calculations rationalize the metal–support interaction with electron transfer from Ru nanoparticles to S,N-codoped carbon matrix, therefore modifying the binding characteristics of intermediates toward the intrinsic activity enhancement.