title: Direct Plasmon-Driven Photoelectrocatalysis.
abstract: Harnessing the energy from hot charge carriers is an emerging research area with the potential to improve energy conversion technologies.1-3 Here we present a novel plasmonic photoelectrode architecture carefully designed to drive photocatalytic reactions by efficient, nonradiative plasmon decay into hot carriers. In contrast to past work, our architecture does not utilize a Schottky junction, the commonly used building block to collect hot carriers. Instead, we observed large photocurrents from a Schottky-free junction due to direct hot electron injection from plasmonic gold nanoparticles into the reactant species upon plasmon decay. The key ingredients of our approach are (i) an architecture for increased light absorption inspired by optical impedance matching concepts,4 (ii) carrier separation by a selective transport layer, and (iii) efficient hot-carrier generation and injection from small plasmonic Au nanoparticles to adsorbed water molecules. We also investigated the quantum efficiency of hot electron injection for different particle diameters to elucidate potential quantum effects while keeping the plasmon resonance frequency unchanged. Interestingly, our studies did not reveal differences in the hot-electron generation and injection efficiencies for the investigated particle dimensions and plasmon resonances.
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Materials Science and NanoEngineering, §Department of Chemistry, ∥Laboratory for Nanophotonics, and ⊥Rice Quantum Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Hossein
authors.initials: H
authors.lastname: Robatjazi
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Materials Science and NanoEngineering, §Department of Chemistry, ∥Laboratory for Nanophotonics, and ⊥Rice Quantum Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Shah Mohammad
authors.initials: SM
authors.lastname: Bahauddin
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Materials Science and NanoEngineering, §Department of Chemistry, ∥Laboratory for Nanophotonics, and ⊥Rice Quantum Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Chloe
authors.initials: C
authors.lastname: Doiron
authors.affiliation: Department of Electrical and Computer Engineering, ‡Department of Materials Science and NanoEngineering, §Department of Chemistry, ∥Laboratory for Nanophotonics, and ⊥Rice Quantum Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
authors.forename: Isabell
authors.initials: I
authors.lastname: Thomann
keywords: Au/NiOx; Plasmonic solar energy conversion; hot-electron; quantum efficiency; selective transport layer; solar water splitting