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Huge Seebeck coefficients in nonaqueous electrolytes
M Bonetti1, S Nakamae, M Roger
1Service de Physique de l'Etat Condensé, CEA-IRAMIS-SPEC (CNRS-MPPU-URA 2464) CEA-Saclay, F-91191 Gif-sur-Yvette Cedex, France. marco.bonetti@cea.fr
The Journal of Chemical Physics
|March 25, 2011
Summary
Researchers measured Seebeck coefficients in nonaqueous electrolytes, finding unusually high values for tetrabutylammonium nitrate in 1-dodecanol. These results suggest significant structure-making effects of tetraalkylammonium ions on alcohol solvents.
Area of Science:
- Physical Chemistry
- Materials Science
- Electrochemistry
Background:
- The Seebeck coefficient quantifies thermoelectric voltage generated by a temperature gradient.
- Aqueous solutions of inorganic ions typically exhibit Seebeck coefficients in the microvolts per Kelvin range.
- Understanding thermoelectric properties of nonaqueous electrolytes is crucial for advanced energy applications.
Purpose of the Study:
- To measure the Seebeck coefficients of specific nonaqueous electrolytes.
- To investigate the influence of tetraalkylammonium ions on alcohol solvent structure.
- To explore potential for high thermoelectric performance in nonaqueous systems.
Main Methods:
- Measurement of Seebeck coefficients for tetrabutylammonium nitrate, tetraoctylphosphonium bromide, and tetradodecylammonium nitrate.
- Electrolyte preparation in nonaqueous solvents: 1-octanol, 1-dodecanol, and ethylene glycol.
- Temperature-dependent measurements conducted between 30°C and 45°C.
Main Results:
- Observed Seebeck coefficients of several hundreds of microvolts per Kelvin for various electrolytes.
- Reported exceptionally high Seebeck coefficients, reaching 7 mV/K at 0.1 M concentration for tetrabutylammonium nitrate in 1-dodecanol.
- Demonstrated significantly larger values compared to typical aqueous inorganic ion solutions.
Conclusions:
- Tetraalkylammonium ions exhibit substantial kosmotropic (structure-making) effects on alcohol solvents.
- The observed high Seebeck coefficients indicate promising thermoelectric properties of these nonaqueous electrolytes.
- These findings open new avenues for research in thermoelectric materials and energy harvesting.
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