Aqueous Phase Methanol Reforming Catalyzed by Fe–Cu Alloy Nanoparticles Wrapped on Nitrogen-Doped Graphene

Small Fe–Cu nanoparticles (NPs) (about 1 nm) supported at a high loading (over 10 wt %) on N-doped graphitic carbon have been prepared in a single pyrolytic step from chitosan adsorbing Cu²⁺ and Fe²⁺ salts. The presence of N atoms appears to be crucial in the formation of small-sized metallic NPs. Interactions between Fe and Cu are reflected by a shift in the binding energy to higher (Fe) or lower (Cu) values and by H₂ thermo-programmed reduction measurements, showing a new reduction peak at intermediate temperature (375 °C) between that of Cu (175 °C) and that of Fe (450 °C). Fe–Cu NPs embedded within the N-doped graphitic carbon matrix are extremely active (TOF 315 h^–1) and selective (no CO detected) catalysts for methanol reforming in the aqueous phase with stoichiometric H₂O amounts to H₂ and CO₂. The results achieved with Fe–Cu compare favorably with those reported in the literature for catalysts based on Pt, Pd, or Ru.