Photocatalytic few atoms Ag nanoclusters produced by ultrashort light pulses

MUÑETÓN ARBOLEDA, DAVID; SANTILLÁN, JESICA MARÍA JOSÉ; MURACA, DIEGO; SCHINCA, DANIEL CARLOS; SCAFFARDI, LUCIA BEATRIZ

Congreso; Photonics Online Meetup 2020; 2020

We have implemented ultrafast laser ablation synthesis in liquids together with mechanical centrifugation to obtain ligand-free silvernanoclusters (Ag NCs). Given the nature of this technique, the NCs colloids produced are highly pure which avoids additional cleaningprotocols. The mechanical centrifugation of the colloids helps to separate the NCs from their larger counterparts (nanoparticles (NPs)),present in the suspension. Synthesized NC colloids are studied by fluorescence spectroscopy observing UV bands corresponding withHOMO-LUMO cluster transitions, and HRTEM measurements where Ag NCs clouds and Ag atomic clusters are observed. Finally, thephotocatalytic response of the Ag NCs was studied by the degradation of the standard molecule Methylene Blue (MB) in interactionwith white light. It was observed that when MB and Ag NCs are mixed in the solution, degradation of MB is much faster, indicatingthe strong photocatalytic response of NCs, even at low concentrations.