Direct Synthesis of H₂O₂ by Spatially Separate Hydrogen and Oxygen Activation Sites on Tailored Pt-Au Catalysts

The direct synthesis of H₂O₂ is considered an atom-efficient, environmentally friendly, and sustainable alternative to replace the current industrial route of the anthraquinone oxidation process. To date a viable direct replacement for the current industrial method of H₂O₂ production has yet to emerge, owing to the strong dissociation abilities of traditional Pd-based catalysts for both H₂ and O₂, which results in the over hydrogenation of H₂O₂ and limited catalytic activity. To address these concerns, this work outlines a novel non-Pd-based catalyst (Pt₁Au_n/TiO₂), consisting of spatially separated H₂ and O₂ activation sites, which offers H₂O₂ selectivity (∼100%) and productivity (128.6 mol·g_N.M. ^-1·h^-1), in excess of state-of-the-art formulations. Crucially, via consecutive reactions, this system achieves net H₂O₂ concentrations approaching 4 wt.%, which is double that generated in the initial stages of the Anthraquinone Oxidation Process. A detailed mechanistic study indicates that Pt single atoms selectively dissociate H₂, while Au nanoparticles stabilize non-dissociative *O₂ ^- species. The H₂O₂ formation proceeds through CH₂O-mediated hydrogen transfer, generating a hydrogen carrier (*CH₂OH) that subsequently reacts with *O₂ ^- to produce H₂O₂.