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Updated: Mar 13, 2026
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Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
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Electron-electrophile coupled dinitrogen reduction in a cerium-meta-tetraphenolate system: a computational study.
Shahbaz Ahmad1, Polly L Arnold2, Nikolas Kaltsoyannis1
1Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK. nikolas.kaltsoyannis@manchester.ac.uk.
Physical Chemistry Chemical Physics : PCCP
|March 12, 2026
Summary
Lanthanide complexes catalyze dinitrogen reduction. Alkali metal coordination and coupled electron-electrophile transfer are key for rare-earth-mediated dinitrogen functionalization, enabling N-N bond cleavage.
Area of Science:
- Homogeneous catalysis
- Organometallic chemistry
- Computational chemistry
Background:
- Catalytic dinitrogen reduction is crucial for nitrogen fixation.
- Lanthanide complexes offer novel catalytic possibilities.
- Understanding reaction mechanisms is key to catalyst design.
Purpose of the Study:
- Elucidate the mechanism of dinitrogen reduction and silylation using a cerium phenolate catalyst.
- Investigate the role of alkali metals and electrophiles in the catalytic cycle.
- Determine key factors for efficient rare-earth-mediated dinitrogen functionalization.
Main Methods:
- Density functional theory (DFT) calculations.
- Modeling of sequential reduction-silylation steps.
- Analysis of reaction energetics and intermediates.
Main Results:
- The first two-electron reduction step is unfavorable without potassium cations (K+).
- N-Si bond formation is unfavorable at the two-electron stage.
- A six-step reduction-silylation pathway cleaves the N-N bond, yielding N(SiMe3)3.
- The highest energy barrier for the catalytic cycle is 22 kcal mol-1.
Conclusions:
- Alkali metal coordination is essential for efficient dinitrogen reduction.
- Coupled electron-electrophile transfer is a critical design principle.
- Rare-earth-mediated dinitrogen functionalization is a promising catalytic strategy.
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