Abstract

A model is established for understanding the temperature change of an alternate hot and cold micro-band graphite electrode. It consists of two symmetrically placed thermoelectric coolers with an embedded graphite sheet as interlayer. By measuring the open circuit behaviors of a standard redox couple, the electrode surface temperature can be detected. And the electrode surface temperature can be regulated from 40°C to −10°C in aqueous solution without freezing. The model is described as Qh=γh ΔT, Qc=γc ΔT, where the temperature change (ΔT) of electrode surface is assumed to be proportional to power of heating (Qh) or cooling (Qc). In addition, the diffusion activation energy of ferricyanide ion is firstly achieved by extending the temperature range from above zero degree down to the supercooled temperature (−10°C) with this specially designed electrode. Diffusion coefficient of ferricyanide ion is ca. 0.22×10−5cm2s−1 at −10°C, and activation energy is 23.2kJmol−1. The experimental data are consistent with data obtained by Stokes–Einstein equation for the determination of diffusion coefficient and activation energy.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.