Can charged colloidal particles increase the thermoelectric energy conversion efficiency?. Issue 14 (22nd March 2017)

• Record Type: Journal Article
• Authors: Salez, Thomas J.; Huang, Bo Tao; Rietjens, Maud; Bonetti, Marco; Wiertel-Gasquet, Cécile; Roger, Michel; Filomeno, Cleber Lopes; Dubois, Emmanuelle; Perzynski, Régine; Nakamae, Sawako
• Is Part Of: Physical chemistry chemical physics. Volume 19:Issue 14(2017)
• Page Start: 9409
• Page End: 9416
• Publication Date: 2017-03-22
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c7cp01023k
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : We show that charged colloidal particles can be used to increase the thermoelectric energy conversion of a thermocell. Abstract : Currently, liquid thermocells are receiving increasing attention as an inexpensive alternative to conventional solid-state thermoelectrics for low-grade waste heat recovery applications. Here we present a novel path to increase the Seebeck coefficient of liquid thermoelectric materials using charged colloidal suspensions; namely, ionically stabilized magnetic nanoparticles (ferrofluids) dispersed in aqueous potassium ferro-/ferri-cyanide electrolytes. The dependency of thermoelectric potential on experimental parameters such as nanoparticle concentration and types of solute ions (lithium citrate and tetrabutylammonium citrate) is examined to reveal the relative contributions from the thermogalvanic potential of redox couples and the entropy of transfer of nanoparticles and ions. The results show that under specific ionic conditions, the inclusion of magnetic nanoparticles can lead to an enhancement of the ferrofluid's initial Seebeck coefficient by 15% (at a nanoparticle volume fraction of ∼1%). Based on these observations, some practical directions are given on which ionic and colloidal parameters to adjust for improving the Seebeck coefficients of liquid thermoelectric materials.