Design-controlled synthesis of IrO2 sub-monolayers on Au nanoflowers: marrying plasmonic and electrocatalytic properties

• DOI: 10.1039/d0nr01875a
• Publication Date: 2020-04-14T10:03:25Z
• Authors: Isabel C. de Freitas; Luanna S. Parreira; Eduardo C. M. Bar...; Barbara A. Novaes; Tong Mou; Tiago. V. Alves; Jhon Quiroz; Yi-Chi Wang; Thomas J. Slater; Andrew Thomas; Bin Wang; Sarah J. Haigh; Pedro H. C. Camargo
• Keywords: Oxygen evolution; Plasmonic Nanoparticles; Visible spectrum

We develop herein plasmonic-catalytic Au-IrO2 nanostructures with a morphology optimized for efficient light harvesting and catalytic surface area; the nanoparticles have nanoflower morphology, closely spaced Au branches all partially covered by an ultrathin (1 nm) IrO2 shell. This nanoparticle architecture optimizes optical features due to interactions of plasmonic forming electromagnetic hot spots, ultra-thin layer maximizes use this expensive catalyst. concept was evaluated towards enhancement electrocatalytic performances oxygen evolution reaction (OER) as model transformation. The OER can play central role in meeting future energy demands but performance conventional electrocatalysts is limited sluggish kinetics. demonstrate improvement one most active catalysts, IrO2, effects from visible illumination multimetallic nanoparticles. find that activity nanoflowers be improved under LSPR excitation, matching best properties reported literature. Our simulations data activities attributed electronic interaction between activation Ir-O bonds excited holes, leading change mechanism (rate-determinant step) illumination.