CAS: Hydrogen Evolution in Water Catalyzed by Molecular Cobalt Complexes with Pentadentate Ligands

With the support of the Chemical Catalysis program in the Division of Chemistry, Dr. Xuan Zhao of The University of Memphis is studying hydrogen production from water as a promising approach to generate this alternative, clean and renewable fuel for the future. Discoveries from the proposed research will have the potential to realize scalable hydrogen production from water using well-defined metal catalysts.

The proposed study will impact the scientific community and society by the generation of new fundamental science, the training of graduate and undergraduate researchers, and the dissemination of the importance of renewable energy research. Undergraduate students in the Memphis region, particularly underrepresented minorities, will have an opportunity to participate in the summer research program in the PI's laboratory.

In addition, annual workshops on solar and renewable energy research will be offered to undergraduate students in the Memphis area. This outreach activity will introduce young researchers to challenges at the forefront of solar energy conversion and inspire them to pursue careers in the field of renewable energy research.

With the support of the Chemical Catalysis program in the Division of Chemistry, Dr. Xuan Zhao of The University of Memphis is studying the basic science of hydrogen evolution reaction catalyzed by molecular cobalt complexes with pentadentate ligands. Based on thermodynamic and kinetic analyses, systematic ligand variations will allow the evaluation of electronic and steric factors that contribute to catalytic activity for hydrogen production.

The proposed study will employ advanced transient spectroscopic techniques (pulse radiolysis, laser flash photolysis and time-resolved infrared spectroscopy) and density functional theory calculations to identify and characterize the electronic structures of critical catalytic intermediates that are important for H–H bond formation. In the context of future applications in renewable energy conversion, the success of this program will lead to the discovery of new catalysts with high efficiency and stability for aqueous hydrogen production at wide range of pHs, including in alkaline solutions.

New ligands and metal compounds created from this program will also impact fundamental studies in other energy-related research such as carbon dioxide reduction, functionalization of hydrocarbons, and green chemistry catalysis.

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.