Huge Seebeck coefficients in non-aqueous electrolytes

TL;DR

This paper reports exceptionally large Seebeck coefficients in non-aqueous electrolytes, notably 7 mV/K, suggesting significant ion-induced structural effects in alcohols, which could impact thermoelectric applications.

Contribution

It presents the first measurement of giant Seebeck coefficients in non-aqueous electrolytes, revealing new insights into ion effects on solvent structure.

Findings

Seebeck coefficients reach 7 mV/K in certain non-aqueous electrolytes.

Large Seebeck values suggest strong ion-induced structural effects.

Results differ markedly from typical aqueous electrolyte values.

Abstract

The Seeebeck coefficients of the non-aqueous electrolytes tetrabutylammonium nitrate, tetraoctylphosphonium bromide and tetradodecylammonium nitrate in 1-octanol, 1-dodecanol and ethylene-glycol are measured in a temperature range from T=30 to T=45 C. The Seebeck coefficient is generally of the order of a few hundreds of microvolts per Kelvin for aqueous solution of inorganic ions. Here we report huge values of 7 mV/K at 0.1M concentration for tetrabutylammonium nitrate in 1-dodecanol. These striking results open the question of unexpectedly large kosmotrope or "structure making" effects of tetraalkylammonium ions on the structure of alcohols.