Public Abstract

DE-SC0016442: Novel Homogeneous Electrocatalysts for the Nitrogen Reduction Reaction

Award Status: Inactive

Institution: Board of Regents of the University of Wisconsin System, operating as University of Wisconsin-Madison, Madison, WI
UEI: LCLSJAGTNZQ7
DUNS: 161202122

Most Recent Award Date: 08/07/2018
Number of Support Periods: 3
PM: Schwartz, Viviane

Current Budget Period: 09/15/2018 - 09/14/2019
Current Project Period: 09/15/2016 - 09/14/2019
PI: Berry, John

Supplement Budget Period: N/A

Public Abstract

Novel Homogeneous Electrocatalysts for the Nitrogen Reduction Reaction John F. Berry, Department of Chemistry, University of Wisconsin-Madison Ammonia (NH₃) is produced industrially on a scale of ~ 150 Mton/yr, expelling roughly 450 Mton/yr of fossil-fuel-derived CO₂ as a byproduct of the hydrogen synthesis step. New, alternative, carbon-neutral approaches to NH₃ synthesis are needed in order to decrease the carbon footprint of this extremely important industrial process. Inspired by the nitrogenase class of enzymes, molecular chemists have discovered several exciting systems that produce NH₃ via homogeneous catalysis that utilize expensive and specialized reagents. A grand challenge in homogeneous ammonia synthesis is to develop catalysts for the nitrogen reduction reaction (N₂RR: N₂ + 6 H⁺ + 6 e^– → 2 NH₃), which could be used to produce ammonia from cheap acids and electricity. The goal of this research project is to explore the feasibility of the elementary steps necessary for the N₂RR using a set of novel compounds based on transition metals that are stable in the presence of protons, electrons, and ammonia, and can undergo several successive redox transformations. Metal-metal bonds imbue these catalysts with strong Lewis acidic character but kinetic lability, ideal for fast and reversible substrate binding necessary for fast catalytic turnover. Aside from the chemical challenges, electrocatalytic N₂RR will be a major engineering challenge; screening for successful electrochemical conditions and design of electrochemical cells will be performed to generate useful knowledge of successful reaction conditions for any potential class of catalysts for the N₂RR.

Novel Homogeneous Electrocatalysts for the Nitrogen Reduction Reaction

John F. Berry, Department of Chemistry, University of Wisconsin-Madison

Ammonia (NH₃) is produced industrially on a scale of ~ 150 Mton/yr, expelling roughly 450 Mton/yr of fossil-fuel-derived CO₂ as a byproduct of the hydrogen synthesis step. New, alternative, carbon-neutral approaches to NH₃ synthesis are needed in order to decrease the carbon footprint of this extremely important industrial process. Inspired by the nitrogenase class of enzymes, molecular chemists have discovered several exciting systems that produce NH₃ via homogeneous catalysis that utilize expensive and specialized reagents. A grand challenge in homogeneous ammonia synthesis is to develop catalysts for the nitrogen reduction reaction (N₂RR: N₂ + 6 H⁺ + 6 e^– → 2 NH₃), which could be used to produce ammonia from cheap acids and electricity. The goal of this research project is to explore the feasibility of the elementary steps necessary for the N₂RR using a set of novel compounds based on transition metals that are stable in the presence of protons, electrons, and ammonia, and can undergo several successive redox transformations. Metal-metal bonds imbue these catalysts with strong Lewis acidic character but kinetic lability, ideal for fast and reversible substrate binding necessary for fast catalytic turnover. Aside from the chemical challenges, electrocatalytic N₂RR will be a major engineering challenge; screening for successful electrochemical conditions and design of electrochemical cells will be performed to generate useful knowledge of successful reaction conditions for any potential class of catalysts for the N₂RR.