Suzuki-Miyaura Cross-Coupling Using Plasmonic Pd-Decorated Au Nanorods as Catalyst: A Study on the Contribution of Laser Illumination

Graphical Abstract

Light or heat? The individual contributions of photochemistry and photothermal heating on a Suzuki-Miyaura cross-coupling reaction of Pd−Au nanorods under laser illumination has been evaluated. It was found that thermal energy dominates the kinetics of this reaction. Additionally, palladium leaching from the photocatalyst was found to play a large role in the overall reaction process.

Abstract

The interaction between plasmonic metal catalysts and visible light can be exploited to increase their catalytic activity. This activity increase results from the generation of hot charge carriers or hot surfaces, or a combination of both. We have studied the light-induced Suzuki-Miyaura cross-coupling reaction of bromobenzene and m-tolylboronic acid using Pd-decorated Au nanorods as plasmonic catalyst in order to assess which physical effect dominates. Comparative experiments under laser illumination and in dark were performed, demonstrating that under the experimental conditions applied in our study the catalytic activity achieved upon illumination is dominantly based on the conversion of light to heat by the plasmonic catalyst. Pd leached from the catalyst also plays a significant role in the reaction mechanism.