Highly Dispersed Palladium Nanoparticles on Silica Spheres for Photocatalytic Hydrodeoxygenation of Vanillin

The heterogeneous catalysis of the hydrodeoxygenation (HDO) of vanillin on palladium (Pd) nanoparticles represents a promising process to valorize biomass, although the catalytic reactions usually require high temperature and high pressure of hydrogen gas. The harsh reaction conditions are avoidable by developing a photocatalytic HDO strategy using highly dispersed Pd nanoparticles attached to the surface of silica nanospheres. Intense surface light scattering resonances in the silica nanospheres significantly improve light absorption in the Pd nanoparticles to efficiently generate high-energy hot electrons, lowering the activation energy of HDO reactions to favor the yield of deep HDO of vanillin at ambient temperature and in the atmosphere of 1 atm H-2. The reaction kinetics of the photocatalytic HDO process increases by several orders of magnitude compared to that of the catalytic HDO process in the dark. The present work provides a new design of composite photocatalysts promising to enable efficient HDO of biomass under mild reaction conditions.

Automated summary

Utilizing highly dispersed Pd nanoparticles attached to the surface of silica nanospheres for photocatalytic hydrodeoxygenation (HDO) of vanillin enables efficient deep HDO yield under mild reaction conditions. The reaction kinetics of the photocatalytic HDO process is orders of magnitude higher compared to the catalytic HDO process in the dark.