Hot carrier multiplication in plasmonic photocatalysis
Linan Zhou, Minhan Lou, Junwei Lucas Bao, Chao Zhang, Jun G. Liu, John Mark P. Martirez, Shu Tian, L. Yuan, Dayne F. Swearer, Hossein Robatjazi, Emily A. Carter, Peter Nordlander, Naomi J. Halas
Abstract
exchange reaction photocatalyzed by Cu nanoparticles is driven primarily by thermalized hot carriers. The external quantum yield shows an intriguing S-shaped intensity dependence and exceeds 100% for high light intensities, suggesting that hot carrier multiplication plays a role. A simplified model for the quantum yield of thermalized hot carriers reproduces the observed kinetic features of the reaction, validating our hypothesis of a thermalized hot carrier mechanism. A quantum mechanical study reveals that vibrational excitations of the surface Cu-H bond is the likely activation mechanism, further supporting the effectiveness of low-energy thermalized hot carriers in photocatalyzing this reaction.