Collaborative Research: CAS-Climate: Structure, Dynamics, and Reaction Mechanism of Supported Single Atom for Photocatalytic CO2 Reduction

In this collaborative project, funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Professor Jier Huang of the Department of Chemistry at Marquette University and Professor Jing Gu of the Department of Chemistry at San Diego State University aim to construct and investigate new generation single atom catalysts for visible light driven carbon dioxide (CO2) reduction to form chemical fuels with high efficiency, selectivity, and stability. Photocatalytic CO2 reduction by harnessing solar energy represents one of the most attractive strategies that may simultaneously address the global warming issue and fulfill the future energy demand. The research is supplemented by diverse educational and outreach activities, including encouraging graduate and undergraduate students, especially underrepresented minority groups, into careers in STEM research, and providing opportunities for students/teachers ranging from elementary to high schools to advance their general understanding of catalysis and renewable energy technologies. Supported single atoms (SAs) have emerged as a novel class of catalysts, offering new promise for light-driven CO2 reduction. The focus of prior research is largely on documenting the efficiency, stability, and the selectivity of the catalysts, not the fundamental mechanistic studies that underlines the correlation of SA structure and their photocatalytic performance. To address such gaps in knowledge, Professor Gu and Professor Huang target the following objectives by leveraging their complementary expertise in materials design and synthesis with time resolved spectroscopy: 1) systematically tuning the geometric and electronic structures of supported SAs via altering the intrinsic nature of SAs, the metal-support interaction, and the comparison with nanoparticles with various sizes; 2) examining the charge separation and structural dynamics, and resolving the intermediate structures at catalytic active sites with high temporal and spatial resolution using time resolved optical and X-ray absorption spectroscopy; and 3) evaluating the direct correlation of the structures of the supported SA catalysts with their photophysical properties and catalytic function to establish structure-property-function relationships for CO2 reduction. Results obtained from these efforts will be of significant value in developing more effective supported SAs for photocatalytic CO2 reduction. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.