玻碳电极表面复合配位银电结晶机理研究
收稿日期: 2018-01-05
修回日期: 2018-03-12
网络出版日期: 2018-04-04
基金资助
国家自然科学基金项目(No. 21621091)
Complex Coordination Silver Electrocrystallization Mechanism on Glassy Carbon Electrode Surface
Received date: 2018-01-05
Revised date: 2018-03-12
Online published: 2018-04-04
Supported by
National Natural Science Foundation of China(No. 21621091)
黄帅帅 , 刘诚 , 金磊 , 杨防祖 , 田中群 , 周绍民 . 玻碳电极表面复合配位银电结晶机理研究[J]. 电化学, 2018 , 24(4) : 344 -350 . DOI: 10.13208/j.electrochem.180105
Cyclic voltammetry and potential step methods were successfully used to study the electrochemical crystallization mechanism of silver deposition on glassy carbon electrode (GCE) in the practical cyanide-free silver plating electrolyte containing composite complexing agents. Scharifker-Hill (SH) theory was used to fitting the experimental data. The results showed that the electrodeposition of silver is a diffusion controlled irreversible electrode process according to three-dimensional instantaneous nucleation mechanism. When the step potential shifted from -750 mV to -825 mV, the peak deposition current Im was increased, while the induced nucleation time tm shortened. The calculated kinetic parameters showed that the diffusion coefficient (D) was basically constant, ranged (7.31 ±0.34) ×10-5 cm2·s-1, and the active nucleation sites density (N0) increased from 3.26 ±105 cm-2 to 10.2±105 cm-2. The morphologies for the initial deposition of Ag verified the three-dimensional instantaneous nucleation mechanism. Increasing the temperature could significantly improve the diffusion ability of the active silver coordination ions in the electrolyte, which shortened the nucleation time and enhanced the active nucleation sites density N0.
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