Monitoring plasmonic hot-carrier chemical reactions at the single particle level

SIMONCELLI, SABRINA; PENSA, EVANGELINA L.; BRICK, THOMAS; GARGIULO, JULIAN; LAURI, ALBERTO; CAMBIASSO, JAVIER; LI, YI; MAIER, STEFAN A.; CORTÉS, EMILIANO

Faraday Discussions

Royal Society of Chemistry

Año: 2018 vol. 214 p. 73 - 87

1359-6640

Plasmon excitation in metal nanoparticles triggers the generation of highly energetic charge carriers that, when properly manipulated and exploited, can mediate chemical reactions. Single-particle techniques are key to unearthing the underlying mechanisms of hot-carrier generation, transport and injection, as well as to disentangling the role of the temperature increase and the enhanced near-field at the nanoparticle-molecule interface. Gaining nanoscopic insight into these processes and their interplay could aid in the rational design of plasmonic photocatalysts. Here, we present three different approaches to monitor hot-carrier reactivity at the single-particle level. We use a combination of dark-field microscopy and photoelectrochemistry to track a hot-hole driven reaction on a single Au nanoparticle. We image hot-electron reactivity with sub-particle spatial resolution using nanoscopy techniques. Finally, we push the limits by looking for a hot-electron induced chemical reaction that generates a fluorescent product, which should enable imaging plasmonic photocatalysis at the single-particle and single-molecule levels.