In situ surface enhanced Raman scattering shows ligand enhanced hot electron harvesting on silver, gold, and copper nanoparticles

Hot carriers electrons and holes generated from the decay of localized surface plasmon resonances can take a major role in catalytic reactions on metal nanoparticles. By obtaining surface enhanced Raman scattering spectra of p aminothiophenol as product of the reduction of p nitrothiophenol by hot electrons, catalytic activity is revealed for nanoparticles of silver, gold, and copper. Different amounts of the product are formed for the different metal nanoparticles. Specifically, we report that a series of different ligands, comprising halide and non halide species, enhance product formation in the reduction reaction. A comparison with the electrode potentials of the metals with and without the ligands indicates that the higher catalytic activity can be associated with a higher Fermi level, thereby resulting in an improved efficiency of hot carrier generation. The concept of ligand enhanced hot electron reduction provides a way to make light to chemical energy conversion more efficient due to improved electron harvestin