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DOE OSTI · 1607484

Light-Controlled Nanoparticle Collision Experiments

Wang, Qian·Bae, Je Hyun·Nepomnyashchii, Alexander B.·Jia, Rui·Zhang, Suojiang·Mirkin, Michael V.
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Abstract

Electrochemical monitoring of catalytically amplified collisions of individual metal nanoparticles (NP) with ultramicroelectrodes (UME) has been extensively used to study electrocatalysis, mass-transport, and charge-transfer processes at the single NP level. More recently, photoelectrochemical collision experiments were carried out with semiconductive NPs. Here we introduce two new types of light-controlled nano-impact experiments. The first experiment involves localized photodeposition of catalyst (Pt) on TiO 2 NPs with a glass-sheathed carbon fiber simultaneously serving as the light guide and collector UME. The collisions of in situ prepared Pt@TiO 2 NPs with the carbon surface produced blips of water oxidation current, while the activity of pristine TiO 2 NPs was too low to yield measurable signal. In another experiment, collisions of catalytic (Ir oxide) NPs with the semiconductor (Nb doped n-type TiO 2 rutile single crystal) electrode are monitored by measuring the photocurrent of water oxidation.

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14 SOLAR ENERGY37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCollisionsLightOxidesPlatinumRadiology

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Wang, Qian, Bae, Je Hyun, Nepomnyashchii, Alexander B., Jia, Rui, Zhang, Suojiang, Mirkin, Michael V.. 2020-03-27. Light-Controlled Nanoparticle Collision Experiments. https://doi.org/10.1021/acs.jpclett.0c00585

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