Plasmonic Nanoantenna Electrodes for Probing Solar Fuel Catalysis

Abstract

Solar fuels – fuels derived from abundant feedstocks by using solar energy – are indispensable for the implementation of a carbon-neutral economy. The water oxidation reaction and the conversion of carbon dioxide to hydrocarbons are two reactions that are central to the production of solar fuels. However, the two reactions are slow. They need to be facilitated by catalysts. Electrocatalysis, an area of catalysis that utilizes electrical energy, is a particularly promising way for promoting these reactions. However, despite their great promise, economically viable electrocatalysts for these reactions are lacking to date. The principal hurdle for the development of efficient electrocatalysts (electrodes) is the poor understanding of how these complex reactions proceed on the electrode surface. The reason for this poor understanding is the insufficient detection sensitivity of existing methods for probing these reactions. The goal of this project is to develop an experimental platform that will yield transformative insights into solar fuel synthesis. Specifically, we will fabricate plasmonic nanoarray electrodes that enhance the optical signals from reaction species by several orders of magnitude in comparison with the current state of the art. The technique is based on the interaction of infrared (IR) light with matter, which permits the identification of reactive species on the electrode surface. We anticipate that the devices will also find applications as voltage-controlled IR sensors.