Abstract:

Silver-plated graphite electrodes were prepared by the absorption method and its surface structure was characterized by SEM assembled with energy dispersive spectrometer.The electrochemical behavior of Sulfur Black 2BR 200% on graphite and silver-plated graphite was studied with linear sweep voltammograms.Experimental results showed that metal silver was successfully coated on the surface of graphite and silver-plated graphite electrode gave higher current and showed better catalytic property for the reduction of Sulfur Black 2BR 200%.In addition, the rate of reduction reaction of Sulfur Black increased with increasing pH of electrolyte.The electrolysis experiments were performed by using graphite and silver-plated graphite cathodes respectively.Excellent current efficiency (92.2%) was obtained in the following reaction condition: silver-plated graphite used as cathode，temperature（27±2）℃, current density 6.25 mA•cm^-2，pH of electrolyte 14.

Key words:

染色, 还原染料, 直接电化学还原, 硫化黑2BR 200%

摘要：

采用涂附法制备了石墨镀银电极。用配有EDS的扫描电子显微镜(FE-SEM)对石墨镀银电极表面结构进行了表征，以石墨镀银电极和石墨电极为工作电极，采用线性扫描法研究了硫化黑在NaOH溶液中的电化学还原行为，探讨了溶液pH值对硫化黑2BR 200%电还原反应的影响。实验结果表明：用涂附法制备得到的石墨镀银电极表面分布了大量金属银颗粒，该石墨镀银电极对硫化黑2BR 200%的还原反应显示了很高的电催化活性，其电催化活性高于石墨电极；电解液的pH值越大，硫化黑的电还原反应就越容易。在恒电流电解中，以镀银石墨电极为阴极，电流密度为6.25 mA•cm^-2，反应温度为(27±2)℃时，硫化黑的电解实验的电流效率可达92.2%。

关键词:

染色, 还原染料, 直接电化学还原, 硫化黑2BR 200%