Near-field enhancement by plasmonic antennas for photocatalytic Suzuki-Miyaura cross-coupling reactions

• Published in: Journal of catalysis 2021-05, Vol.397, p.205-211
• Main Authors: Han, Chenhui, Gómez, Daniel E., Xiao, Qi, Xu, Jingsan
• Format: Article
• Language: English
• Subjects: Cross-coupling reactions; Near-field enhancement; Plasmonic antennas; Substrates effect; “Antenna-reactor” catalysts
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2021.03.020

[Display omitted] •A “Au antenna-Pd reactor” catalytic system was designed and constructed.•Au antennas enhance Pd activity to Suzuki–Miyaura cross-coupling reactions.•The reactive center electron cloud density of the substrates affects the enhancement.•The enhancement is also decided by the electromagnetic hot spot interactions. It is well documented that placing a plasmonic antenna close to catalytically active nanoparticles can enhance their catalytic activity in chemical reactions via the near-field enhancement effect. Less known is whether and how the near-field enhances the reactivity of the reactant substrates involved in these reactions. Herein, we prepared an “antenna-reactor” catalyst with Au nanoparticles absorbing light as an optical antenna and the adjacent Pd nanoparticles acting as a chemical reactor to study the near-field enhancement effect in Suzuki–Miyaura cross-coupling reaction involving various substrates. The results showed that the activity of Pd nanoparticles were significantly enhanced in the presence of Au antennas. Excessively increasing the density of Au antennas, however, suppressed the reaction due to the interaction between neighboring electromagnetic hot spots. Moreover, the near-field affected different substrates in different extents, enhancing more to reactions that involve substrates with higher electron cloud density at the reactive center. The overall effect of the near-field to the catalytic reactions was proved to be an integrated result of the effect of Au nanoparticle density and reactive center electron cloud density. This study provides enriched understanding for the near-field enhancement effect in photocatalytic reactions with various substrates, and deepened insights for new “antenna-reactor” photocatalyst design.