Development of Electrocatalysts for the Hydrogen Evolution Reaction and CO2 Reductions Reaction
Since 2014, in collaboration with Professor Craig Grapperhaus, Professor Gautam Gupta (Department Chemical Engineering) and Dr. Josh Spurgeon (Conn Center) at UofL, I have examined the catalytic activity of a series of redox non-innocent thiosemicarbazone compounds and their Zn, Cu and Ni complexes for the hydrogen evolution reaction (HER) and CO2 reduction reaction (CO2RR). The electrocatalytic reaction for HER can be ligand-centered (Zn), metal-assisted ligand-centered (Cu) and ligand-assisted metal-centered (Ni) depending on the metal ion and ligand of the complex. Also, we have designed, prepared and characterized thiosemicarbazone ligands that display metal-ligand cooperativity in the binding and reduction of CO2. The Zn complexes capture atmospheric CO2 in methanol forming a metal bound methylcarbonate, which can be converted electrocatalytically to formate. Representative and informative articles on our studies are listed below.
Citations
A. Z Haddad, B. D. Garabato, P. M. Kozlowski, R. M. Buchanan, C. A. Grapperhaus, “Beyond Metal-Hydrides: Non-Transition-Metal and Metal-Free Ligand-Centered Electrocatalytic Hydrogen Evolution and Hydrogen Oxidation.” J Am Chem Soc. 2016 Jun 29;138(25):7844-7. doi: 10.1021/jacs.6b04441.
S. Gulati, O. Hietsoi, C. A. Calvary, J. M. Strain, S. Pishgar, H. C. Brun, C. A. Grapperhaus, R. M. Buchanan, J.M.Spurgeon, ”Photocatalytic hydrogen evolution on Si-photocathodes modified with bis(thiosemicarbazonato)nickel(II)/Nafion,” Chem Comm. 2019, 55, 9440-9443. doi: 10.1039/c9cc04117f.
A. Gupta, N. S. Vishnosky, O. Hietsoi, Y. Losovyj, J. M. Strain, J. M. Spurgeon, M. S. Mashuta, R. Jain, R. M. Buchanan, G. Gupta, C. A. Grapperhaus, “Effect of Stacking Interactions on the Translation of Structurally Related Bis-thiosemicarbazone Ni(II) HER Catalysts to Modified Electrode Surfaces,” Inorg. Chem. 2019, 55, 12025-12039. doi: 10.1021/acs.inorgchem.9b01209.
S. P. Cronin, J. M. Strain, M. S. Mashuta, J. M. Spurgeon, R. M. Buchanan, C. A. Grapperhaus, "Exploiting Metal-Ligand Cooperativity to Sequester, Activate, and Reduce Atmospheric Carbon Dioxide with a Neutral Zinc Complex" Inorg. Chem. 2020, 59, 4835-4841. doi:10.1021/acs.inorgchem.0c00121.
C. A. Phipps, D. T. Hofsommer, M. J. Toda, F. Nkurunziza, B. Shah, J. M. Spurgeon, P. M. Kozlowski, R. M. Buchanan, C. A. Grapperhaus “Ligand-centered hydrogen evolution with Ni(II) and Pd(II) DMTH” 2022. doi: 10.1021/acs.inorgchem.2c01326.
