Quantifying hot carrier and thermal contributions in plasmonic photocatalysis
Linan Zhou, Dayne F. Swearer, Chao Zhang, Hossein Robatjazi, Hangqi Zhao, Luke Henderson, Liangliang Dong, Phillip Christopher, Emily A. Carter, Peter Nordlander, Naomi J. Halas
Abstract
Photocatalysis based on optically active, "plasmonic" metal nanoparticles has emerged as a promising approach to facilitate light-driven chemical conversions under far milder conditions than thermal catalysis. However, an understanding of the relation between thermal and electronic excitations has been lacking. We report the substantial light-induced reduction of the thermal activation barrier for ammonia decomposition on a plasmonic photocatalyst. We introduce the concept of a light-dependent activation barrier to account for the effect of light illumination on electronic and thermal excitations in a single unified picture. This framework provides insight into the specific role of hot carriers in plasmon-mediated photochemistry, which is critically important for designing energy-efficient plasmonic photocatalysts.