title: Voltammetry under a controlled temperature gradient.
abstract: Electrochemical measurements are generally done under isothermal conditions. Here we report on the application of a controlled temperature gradient between the working electrode surface and the solution. Using electrochemical sensors prepared on ceramic materials with extremely high specific heat conductivity, the temperature gradient between the electrode and solution was applied here as a second driving force. This application of the Soret phenomenon increases the mass transfer in the Nernst layer and enables more accurate control of the electrode response enhancement by a combination of diffusion and thermal diffusion. We have thus studied the effect of Soret phenomenon by cyclic voltammetry measurements in ferro/ferricyanide. The time dependence of sensor response disappears when applying the Soret phenomenon, and the complicated shape of the cyclic voltammogram is replaced by a simple exponential curve. We have derived the Cotrell-Soret equation describing the steady-state response with an applied temperature difference.
authors.affiliation: BVT Technologies, a.s., Hudcova 533/78c, 612 00 Brno, Czech Republic. info@bvt.cz
authors.forename: Jan
authors.initials: J
authors.lastname: Krejci
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Sajdlova
authors.forename: Jan
authors.initials: J
authors.lastname: Krejci
authors.forename: Tomas
authors.initials: T
authors.lastname: Marvanek
mesh_terms: D004563:Electrochemistry; D005292:Ferricyanides / Q000737:chemistry; D013696:Temperature
chemical_list: D005292:Ferricyanides; C007931:hexacyanoferrate III