Laser-assisted catalyzed oxidation of glycerol and methanol at room temperature by thermal photo conversion of Plasmonic Gold Nanoparticles (GNPs)
Résumé
Plasmonic nanoparticles can absorb light and convert it to heat, which is thereafter transferred to the surrounding environment. Simultaneously, gold nanoparticles (GNPs) show catalytic activity in many reactions. Therefore, GNPs can serve as both local nanoscale-heat sinks and catalysts to drive chemical reactions. This could in principle be realized by a laser-induced selective excitation of the surface Plasmon resonance of nanoparticles at a particular wavelength. Recently, this principle has been used in order to catalyze the production of 4-benzoylmorpholine from benzaldehyde and morpholine via amide formation. Furthermore, it was used to increase the yield of Suzuki coupling. In the present work, we provide a proof which demonstrates the concept of laser-assisted catalyzed oxidation of glycerol and methanol at room temperature. Alumina supported or unsupported GNPs with different stabilizing agents were used in liquid or gas phase catalytic reactions, respectively. Green laser emitting 2.6 W at 532 nm was used to excite the resonance band of the GNPs. The first experimental investigations show that the laser activation is more advantageous than the conventional macroscopic heating in terms of conversion rate of glycerol and of stability of the catalyst.