Kinetics and Mechanism toward Electrochemical Reductions of Sodium Bromide and Methanol over Iron Electrodes

Authors

Qun LIAO
Shu-feng ZHANG
Wen-hua LENGFollow

Corresponding Author

Wen-hua LENG(lengwh@zju.edu.cn)

Abstract

It is of technological value and scientific interest to the electro-synthesis of ferrocene, conversion of carbon dioxide (CO₂) and organic electro-synthesis in non-aqueous solutions by investigating the kinetics and mechanism toward electrochemical reductions of sodium bromide (NaBr) and methanol over iron electrodes. However, few reports in the related researches are available. In this article, the kinetics and mechanism toward electrochemical reductions of NaBr and methanol over iron electrodes were examined in detail by carrying out the polarization curve and electrochemical impedance spectroscopic measurements. The results showed that methanol was the reactant, while Na⁺ ions were functioned only as conducting species; the electrode potential was the only status variable, and its impact on the rate constants of the electro-reduction of methanol followed classic Arrhenius’s equation; the reduction was not limited by concentration diffusion, but mainly by the Ohmic polarization; the amount of H₂ gas production obeyed the Faraday’s law and the activation energy was evaluated to be ~26.2 kJ•mol^-1.

Graphical Abstract

Keywords

Methanol, Electro-reduction; Sodium Bromide, Electrochemical impedance spectroscopy, Iron electrode

DOI Link

https://doi.org/10.13208/j.electrochem.161017

Publication Date

2017-12-28

Online Available Date

2017-01-03

Revised Date

2016-12-31

Received Date

2016-10-19

Recommended Citation

Qun LIAO, Shu-feng ZHANG, Wen-hua LENG. Kinetics and Mechanism toward Electrochemical Reductions of Sodium Bromide and Methanol over Iron Electrodes[J]. Journal of Electrochemistry, 2017 , 23(6): 161017.
DOI: 10.13208/j.electrochem.161017
Available at: https://jelectrochem.xmu.edu.cn/journal/vol23/iss6/13

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