Research Goals The research outlined in this proposal concerns the development of catalysts capable of supporting the conversion of dinitrogen (N2) to ammonia (NH3) under mild conditions using the Earthabundant metal iron (Fe). Largely due to the demands of food production, industrial generation of NH3 consumes more than 1 % of the world's energy output as a result of the energetically intense conditions employed. Enzymatic NH3 production occurs under ambient temperature and pressure, and translation of this efficiency to a synthetic system would significantly decrease energy production demands. We aim to pursue this goal through a heretofore unexplored reaction manifold designed to maximize N2 activation and minimize the number of intermediates necessary for NH3 production. The interdependent use of experiment and theoretical calculations will be used to realize the secondary objectives of advancing scientific understanding of N2 functionalization and probing the boundaries thereof, understanding the effect of varied electronic structure on N2 reactivity, and exploring new Fe coordination chemistry. Fixation and functionalization of the relatively inert dinitrogen (N2) molecule has been studied extensively for over 40 years, but well-defined abiological catalytic conversion to ammonia (NH3) under mild conditions has remained an elusive target. The conversion of N2 to NH3 is of both fundamental and practical interest as NH3 is a critical component of food production and controlled functionalization of N2 is a significant challenge in catalyst design due to the varied oxidation states, bonding modes, and reaction conditions that a catalyst must support. The research outlined in this proposal seeks to lower the energetic and economic footprints of NH3 production through development of base metal catalysts that are capable of converting N2 to NH3 under mild conditions. We intend to approach this goal by incorporating lessons learned from previous studies on the bonding and reactivity of N2 and using them to design catalysts that maximize N2 activation and minimize the number of potential intermediates in order to confer robustness to the catalytic cycle. In pursuit of this objective, we also aim to advance the current understanding of how electronic configuration and steric bulk affect the ability of iron (Fe) to reductively cleave N2, functionalize the resulting nitride, and release NH3. These catalyst design characteristics can then be optimized to improve catalyst efficiency and efficacy through a feedback loop of experimental and theoretical investigations.
|Effective start/end date||3/11/13 → 9/30/13|
- US Department of Energy (DOE): $20,000.00