Molecular Coadsorption of p-Hydroxythiophenol on Silver Nanoparticles Boosts the Plasmon-Mediated Decarboxylation Reaction

Surface plasmons have received much attention in chemical reactions because of their high light-utilizing efficiency, high reaction rate, and mild reaction conditions. However, the potential of plasmonic photochemistry has not been fully exploited, mainly due to the limited lifetime of plasmon-generated hot carriers. Herein, using in situ Raman spectroscopy, we reveal that the coadsorption of p-hydroxythiophenol (PHTP) molecules significantly accelerates the plasmon-mediated decarboxylation reaction of p-mercaptobenzoic acid adsorbed on silver nanoparticles. The observed boosting of the decarboxylation reaction is attributed to the matched energy distribution of the plasmon-generated hot electrons to the lowest unoccupied molecular orbital (LUMO) level of the coadsorbed PHTP molecules. Our findings will help not only to deepen the understanding of the plasmon-mediated chemical reactions but also to fabricate highly efficient plasmonic catalysts conveniently and cost-effectively.