【摘要】 在Zn（Ⅱ）-NH₄Cl准中性体系中,采用循环伏安法（CV）研究了Zn²⁺在锌电极上的反应方式,通过计时电流法（CA）研究了Zn²⁺沉积的成核方式,利用交流阻抗谱（EIS）考察了不同过电位时Zn²⁺沉积的阻抗行为。结果表明:Zn²⁺的电沉积是一个不可逆电极反应,以两步骤单电子串联的方式进行,第一步为速控步;电极反应的电荷传递系数与锌电极的表面结构有关。在恒电位条件下,体系中锌电极上Zn²⁺的结晶近似于三维瞬时成核方式。Zn²⁺的沉积经历了覆盖、吸附成膜、大量晶核形成等过程,该过程随着控制电位的负移由电化学极化过渡到电化学极化-浓差极化混合控制阶段。最后给出了Zn²⁺在锌电极上电沉积过程的机理。更多还原

【Abstract】 Reaction method of Zn²⁺on the zinc electrode was researched by cyclic voltammetry（CV）. Nucleation mode with Zn²⁺was studied by chronoammperometry（CA） and impedance′s behavior of the Zn²⁺in the different overpotential deposition periods was investigated by electrochemical impedance spectroscopy（EIS） in Zn（Ⅱ）-NH₄ Cl quasi neutral system. The results showed that the electrodeposition of Zn²⁺is an irreversible electrode reactions and conducts by continuous two steps of single electron in which the first step is controlled by speed.The electron transfer coefficient of electrode reaction is related to the surface of zinc electrode structure. Under the condition of constant potential, the crystallization of Zn²⁺is approximate to three-dimensional instantaneous nucleation on zinc electrode in this system. Depositing of Zn²⁺has experienced the process of covering, adsorption film and the formation of large number of nucleation. The process was controlled by electrochemical polarization firstly and then the electrochemical polarization-concentration polarization mixed control with the control potential negatively shifted. Finally the mechanism of electrodeposition process with Zn²⁺on the zinc electrode was given.更多还原