Multielectron, multisubstrate catalysis is central to energy conversion processes in biology and technology. Catalysts provide low-energy pathways for driving chemical transformations and are utilized in applications ranging from manufacturing fuels and fine-chemicals to controlling the bioenergetics essential to all living organisms. Although the ability to photochemically power energetically uphill reactions using solar energy and catalyst has been demonstrated, finding ways to more effectively immobilize catalysts onto surfaces and characterize the resultant interfaces remains challenging as there is not enough understanding of how charge carriers move through these systems to provide rational design principles. This proposal targets an improved understanding of the fundamental science governing such photo-driven transformations through molecular-level research in the condensed phase and at interfaces. The proposed activities focus on 1) using extended macrocyclic architectures and resulting as a structural motif for the precise synthesis of molecular components with tailored electronic states and enhanced electrocatalytic features favoring not only the electron- but also proton-transfer sequences common to nearly all reactions relevant to solar fuel generation, 2) developing effective methods to immobilize electrocatalysts onto (semi)conducting electrodes, forming hybrid structures that convert light into chemical energy, and 3) applying, developing, and linking surface-characterization techniques with (photo)electrochemical experiments to improve understanding of structure-function relationships governing molecular-modified (semi)conductors and better understand the interplay between light absorption, charge transfer, and catalysis at molecular-modified photoelectrode surfaces. While structurally more complex than their individual components, the proposed hierarchical materials move beyond the use of traditional model systems and towards studying the basic energy science of photoelectrochemically powering catalysts in complex chemical environments.
|Effective start/end date||9/1/20 → 8/31/25|
- DOE: Office of Science (OS): $750,000.00