On the first step in zinc deposition – A case of nonlinear coupling with the solvent

Electrochemistry Communications

Wolfgang Schmickler¹  Fernanda Juarez²  Elizabeth Santos²  Axel Groß²  Gustavo Belletti³  Paola Quaino³  Estefania Colombo³ 

[1] Helmholtz Institute Ulm (HIU), Germany;Institute of Theoretical Chemistry, Ulm University, Germany;Instituto de Química Aplicada del Litoral, IQAL (UNL-CONICET), Santa Fe, Argentina;

关键词: Metal deposition;    Zinc batteries;    Inner-sphere electron transfer;    Nonlinear effects;   

DOI  :  

来源: DOAJ

【 摘 要 】

The deposition of zinc from aqueous solutions is of great practical importance, and it also serves as a prototype for the deposition of divalent ions. Both experiment and theory agree, that it takes place in two steps. Previous theoretical work [1] had suggested that the step, Zn+++e-→Zn+ takes place in the outer sphere, but gave a prohibitively high energy of activation of the order of 1.4 eV, in accord with the enigma of metal deposition postulated by Gileadi [2]. In this work the treatment of the reactant – solvent interaction is substantially improved by introducing nonlinear terms based on molecular dynamics. Our calculations suggest that the first steps follows an inner sphere path with a much lower energy of activation, which results in a physically adsorbed Zn+ ion. The second step then occurs on the electrode surface. These findings are in line with experimental data.

【 授权许可】

Unknown