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

Abstract

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.