This award by the Chemical Catalysis Program in the NSF Division of Chemistry supports the research of Dr. Bradford Wayland of Temple University, who pursues new classes of catalysts for the selective reduction and conversion of carbon monoxide and carbon dioxide into useful organic materials. These chemical transformations can be used to solve major contemporary issues in energy research. The research includes the pursuit of catalysts based on earth-abundant, first transition series metal complexes. Realization of the objectives of the research will advance areas of chemical technology important for long term stability in the production of economical, liquid fuels and chemical feed stocks. The students involved in this research receive excellent training in chemical synthesis and characterization, and chemical catalysis.
The core objective of the research is to utilize bimetallic complexes containing metal-centered radicals to accomplish thermodynamically challenging transformations of carbon monoxide and dioxide. The selection of the metal complexes is guided by thermochemical criteria and DFT computations. The ability to attain productive intermediates for catalysis in mild conditions is tuned by the ligands, which are designed to support bimetallic complexes with minimal metal-metal bonding. Schiff base macrocyclic ligands are being developed as easily prepared, low-cost substitutes for porphyrins. Non-macrocyclic tetradentate ligands provide pathways for migratory insertions that are inhibited in complexes with macrocyclic ligands. A series of anionic tridentate pincer type ligands with pyrrole and imine donors are designed to form metal-centered radicals in which the metal has a d7 or d9 electron configuration. The Pd(I) and Pt(I) derivatives afford the best opportunities to expand the current limits of carbon dioxide activation reactions. The complexes of Ni(I) and Fe(I) are leading candidates to accomplish catalytic conversion of carbon oxides using earth abundant first transition metals.
