Universal Strategy for Ultrathin Pt-M (M = Fe, Co, Ni) Nanowires for Efficient Catalytic Hydrogen Generation

Methanol (CH₃OH) reformation with water (H₂O) to in situ release hydrogen (H₂) is regarded as a hopeful H₂ production approach for polymer electrolyte membrane fuel cells, while developing highly efficient CH₃OH reformation catalysts still remains a great challenge. Herein, a series of Pt-based ultrafine nanowires (UNWs) with high surface atom ratio are used as highly active and stable catalysts for CH₃OH reformation to H₂. By tuning Pt₃M (M = Fe, Co, Ni), support and the composition of the Pt_xFe UNWs, the optimized Pt₄Fe UNWs/Al₂O₃ exhibits excellent catalytic behaviors with the high H₂ turnover frequency reaching to 2035.8 h^-1, more than 4 times higher than that of Pt UNWs/Al₂O₃. The reaction mechanism investigated by diffuse reflectance infrared Fourier transform spectroscopy turns out that the production of H₂ undergoes the CH₃OH decomposition to∗CO and gas-shift reaction of∗CO with H₂O. Combing with the XPS result and the density functional theory calculations, the high CH₃OH reformation activity of Pt₄Fe UNWs/Al₂O₃ is attributable to synergism between Pt and Fe, which facilitates H₂ desorption and intermediate HCOO∗ and∗COO formations via the reaction between∗CO and OH^-. © 2018 American Chemical Society.