(521ec) Plasmonic Photocatalysis By Dynamic Calculations: Mechanisms and Design

Many industrial chemical processes, which require high operating temperatures to drive crucial catalytic reactions, are both energy intensive and detrimental to the long-term life of the catalyst. Plasmonic metals such as Au and Ag have attracted significant attention due to their ability to harness light in the visible spectrum and have been used in a wide variety of applications, including driving catalytic reactions. Gaining insight into the mechanisms occurring in these plasmonic reactions is challenging but important for the rational design of new catalysts. Here, we utilize real-time, time-dependent density functional theory (RT-TDDFT) to excite systems with oscillating electric fields and track the subsequent excited state dynamics in real time. Our work has shown the importance of the near-field enhancement for facilitating the dissociation of small molecules like O₂ and N₂ and the role that charge transfer can play in each case. In this presentation we focus on electron-level design and insights into practical applications of plasmonic photocatalysis such as deoxygenation of biomass-derived molecules using Au and Ag nanoparticles, as well as N₂ activation using so-called “antenna reactors”. We show how these plasmonic systems can be tuned to drive selective chemistry through the targeted activation of C-O bonds by adjusting nanoparticle composition, size and shape as well as the applied electric field frequency and amplitude. Further, we screen Cu-based antenna reactors to discover effective compositions for N₂ activation and gain detailed insights. Overall, this work demonstrates the utility of real-time dynamic computational tools for the discovery and design of novel plasmonic catalysts.