(112d) Engineering the Ptwox Inverse Catalysts By Tuning the Wox Coverage

Selective C-O bond activation in biomass valorization is often hypothesized to proceed on bifunctional active sites. Bifunctional active sites have been established on metal-metal oxide inverse catalysts. However, deciphering the function of individual sites on inverse catalysts is challenging due to a complex interplay of nanoparticle size and morphology, the acidity of metal oxide and coverages on metals, and the synergy between them. Here, we overcome these limitations by synthesizing silica-supported, metal coverage finely tuned Pt-WO_x inverse catalysts. Leveraging various probe chemistries, reaction kinetics, in situ spectroscopy, and density functional theory calculations, we unveil that WO_x loadings on Pt terrace are controlled by Pt particle sizes. WO_x overlayers can effectively block well-coordinated Pt terraces, allowing for the modulation of site density. The Pt-WO_x inverse pairs catalyze the ring opening of tetrahydrofurfuryl alcohol via a bifunctional mechanism that encompasses Brønsted acid sites and metal sites, displaying a volcano-shaped activity trend. Our findings herald a significant stride towards synthesizing site-controlled catalysts, offering a tailored pathway to enhance catalyst performance through precise site engineering.