Actual activation energy of electrode process under mixed kinetics conditions

作者：Danilov F I^*; Protsenko V S

来源：Russian Journal of Electrochemistry, 2009, 45(10): 1105-1114.

DOI：10.1134/S1023193509100012

• activation energy
• electrochemical reaction
• electrode potential
• Arrhenius equation

In the case of a single-electron reaction with account for slow diffusion of reagents, equations for actual (experimentally determined) activation energies of two types were derived and analyzed: real energy A f, i.e., the energy measured at a constant electrode polarization value eta = const) and formal energy (Omega(f), i.e., the value measured at a constant value of potential vs. an ambiguously chosen reference electrode E = const). It is found that under the conditions of a sufficiently significant deviation from equilibrium, the actual activation energy A (f) is the weighted arithmetic mean of the diffusion activation energy and the sum of A (0) alpha F eta (where A (0) is the real activation energy of the discharge stage at polarization of eta = 0); herewith, the weighting coefficients are the corresponding values of the current of the discharge stage and the limiting diffusion current. A similar relationship is also obtained for Omega(f). It is found that the A (f), eta- and Omega(f), E-curves can in a number of cases feature regions with the negative A (f) and Omega(f) values in the mixed kinetics range.

• 出版日期2009-10
• 单位北京化工大学