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Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production
Published on: December 6, 2021
Computational study of anomalous reduction potentials for hydrogen evolution catalyzed by cobalt dithiolene complexes
Brian H Solis1, Sharon Hammes-Schiffer
1Department of Chemistry, 600 South Matthews Avenue, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|September 8, 2012
Summary
This study explains why a specific cobalt dithiolene complex is a poor hydrogen-evolving catalyst. Ligand protonation after reduction, not substituent effects, dictates catalytic activity for renewable energy applications.
Area of Science:
- Catalysis
- Renewable Energy
- Computational Chemistry
Background:
- Developing efficient hydrogen-evolving catalysts from earth-abundant materials is crucial for renewable energy.
- Cobalt dithiolene complexes are investigated as potential electrocatalysts.
Purpose of the Study:
- To computationally investigate the anomalous electrocatalytic activity of four hydrogen-evolving cobalt dithiolene complexes.
- To elucidate the mechanism behind the reduced activity of Co(mnt)(2).
Main Methods:
- Computational studies were employed to analyze a series of four cobalt dithiolene complexes.
- The study focused on the role of ligand protonation in electrocatalytic activity.
Main Results:
- Co(mnt)(2) (mnt = maleonitrile-2,3-dithiolate) exhibits the least activity due to less sulfur atom protonation on the dithiolene ligand after initial Co(III/II) reduction.
- This leads to a more negative Co(II/I) reduction potential for Co(mnt)(2).
- A proposed mechanism involves intramolecular proton transfer to form a catalytically active Co(III)-hydride.
Conclusions:
- Ligand protonation significantly impacts the electrocatalytic activity of cobalt dithiolene complexes.
- Understanding these effects is key for designing improved electrocatalysts for solar energy conversion.
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