Pathways for Carbon Dioxide Reduction in Plasmonic Hot Carrier Photoelectrochemical Structures

Harvesting non-equilibrium carriers at semiconductor-metal interfaces offers an opportunity to modify the rates and pathways for photochemical reactions at the nanoscale. The carrier generation, transport and interface dynamics can be addressed with a combination of first-principles theory for carrier excitation and relaxation, observation of carrier dynamics via hot-carrier photocurrent spectroscopy, ultrafast transient absorption spectroscopy, and photoelectrochemical measurements that assess current transport, product yield and selectivity. We use as examples reactions at the Au/p-GaN and Cu/NiO interfaces, both of which feature photoexcited hot hole injection at the metal-p-type wide bandgap semiconductor interface. We compare results of theory to excited carrier transport, transient absorption and photocatalysis measurements in these systems.