Hot carrier multiplication in plasmonic photocatalysis

Significance Photochemical processes on the surfaces of illuminated metallic nanoparticles have shown outstanding efficiencies and may provide new, light-based strategies for inducing chemical transformations that consume far less energy than do conventional heat-driven catalysts. Energetic, or “hot” electrons, play an important role in these types of processes, although their short lifetime has made this interpretation somewhat controversial. In this work, we report a photochemical reaction with an unusually high efficiency that points toward thermalized hot carriers as being the driving force. This study broadens our interpretation of hot-electron–mediated chemical processes and may pave the way for even higher efficiencies in this emerging field of chemistry.