Decoupling geometric effects in furfuryl alcohol hydrogenation by regulating the surface coordination of Pt nanoparticles

Abstract

For structure-sensitive reactions, adsorption behavior is closely related to the coordination environment of active metal sites. However, conventional methods for tuning surface coordination often simultaneously alter the electronic structure of metals, making it difficult to decouple geometric and electronic effects. Herein, we report a gas-phase treatment strategy to selectively regulate the surface coordination of Pt nanoparticles in Pt/TiO 2 catalysts while maintaining similar particle size and electronic properties. Using the hydrogenation of biomass-derived furfuryl alcohol (FFA) as a probe reaction, we demonstrate that H 2 treatment yields a spherical Pt/TiO 2 -H 2 catalyst with abundant under-coordinated Pt sites, which delivers 70% selectivity toward 1,2-pentanediol (1,2-PeD) and shows remarkable stability for over 300 h in a fixed-bed reactor. In contrast, CO treatment produces a truncated octahedral Pt/TiO 2 -CO catalyst with predominantly well-coordinated Pt sites, exhibiting high selectivity (67%) for tetrahydrofurfuryl alcohol. Kinetic studies and density functional theory (DFT) calculations reveal that under-coordinated Pt sites favor a tilted adsorption configuration of FFA and facilitate H 2 dissociation, while well-coordinated Pt sites induce a parallel adsorption of the furan ring and strongly compete with H 2 adsorption. This work provides a facile and organic-capping-free approach for disentangling the geometric role of metal catalysts in structure-sensitive transformations.