Improving the rates of Pd-catalyzed reactions by exciting the surface plasmons of AuPd bimetallic nanotriangles

Abstract

Gold nanoparticles exhibit unique optical properties due to surface plasmon oscillations when they interact with light. By utilizing their optical properties, the rates of many chemical reactions have been improved in the presence of visible light. The properties of plasmonic nanoparticles are highly tunable based on the size and shape of the nanoparticle. Here, we have used anisotropic AuPd bimetallic nanotriangles to improve the rates of Pd-catalyzed reactions in the presence of visible light. We synthesized AuPd core–shell bimetallic nanotriangles and performed Suzuki cross-coupling and hydrogenation reactions in light and dark conditions. Upon illuminating AuPd nanotriangles with an array of green LEDs (power ∼ 500 mW), enhanced catalytic activity of palladium was observed. In order to understand the relative contributions of individual plasmonic effects, such as plasmonic hot electron transfer and plasmonic heating effects, the reaction temperatures were monitored, and careful control experiments were run at different temperatures. Our results indicated that the enhancement in the rate of these Pd-catalyzed reactions is primarily due to the plasmonic heating effect.