Electroreforming of methanol employing in-house prepared PtRu/C anode catalysts for hydrogen generation at the cathode

The increasing global energy demand and the environmental impacts of fossil fuel consumption have driven the exploration of sustainable energy alternatives. Hydrogen is a promising clean energy carrier, particularly when produced via renewable-powered electrolysis. However, the efficiency of conventional water electrolysis is limited by the sluggish kinetics of the oxygen evolution reaction (OER). This study explores methanol electrooxidation as a more energy-efficient anodic alternative to OER in hydrogen generation systems. We synthesized 50 wt% Pt₁Ru₁ catalysts supported on Ketjenblack carbon (PtRu/C) via two sulphite-complex-based routes: (i) sequential impregnation of Ru onto preformed Pt-sulphite complexes, and (ii) direct mixing of Pt- and Ru-sulphite precursors. The resulting catalysts were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) to assess their crystallinity, phase composition, morphology, and surface properties. The electrochemical performance was evaluated through methanol electroreforming experiments conducted in a membrane–electrode assembly (MEA) configuration. Full-cell tests conducted at 90 °C revealed an initial enhancement in performance for the catalyst with Ru impregnated onto Pt-sulphite, despite the presence of some non-alloyed Ru particles. In contrast, the PtRu/C-based MEA prepared by mixing Pt- and Ru-sulphite exhibited superior durability during a 24-h chronopotentiometric test, likely due to Pt Ru alloy formation and the enhanced stability of Ru within the alloy. These results confirm the potential of optimized PtRu/C systems for efficient hydrogen production via methanol electroreforming and highlight the importance of synthesis strategy in tuning electrocatalyst performance and durability. • 50 wt% Pt₁Ru₁/C catalysts were prepared via two sulphite-complex-based routes. • Catalysts were used for methanol electrooxidation in an electroreforming cell. • Methanol electrooxidation is an alternative to oxygen evolution in electrolysis systems.