Exploring Plasmonic Photocatalysis via Single-Molecule Reaction Imaging.

Plasmonic photocatalysis has emerged as a new frontier in heterogeneous catalysis due to its promise in harvesting light to drive reactions. Yet many mechanistic aspects remain to be unambiguously defined. Using single-molecule fluorescence imaging, Li et al. studied a fluorogenic and plasmon-enhanced reaction, amplex red oxidation, on single Au nanorods at subturnover resolution and under operando conditions. Both the rate-determining step and its activation energy were identified from the multiple elemental reactions. The results provide insights into the mechanism of plasmonic photocatalysis that may help the rational design of heterogeneous catalysts.