Benzyl viologen (BV) was deposited at copper in the presence of chloride anions to generate a benzyl viologen-chloride layer at copper, where the viologen was present as a dication, stabilised by the negatively charged chloride anions. This layer provided good protective properties to the underlying copper substrate. On polarising the BV-modified copper in 0.1 M NaCl significantly lower currents, typically 28 μA cm⁻², were observed at 0.40 V vs SCE compared to the higher currents of 1.75 mA cm⁻² evident with the unmodified copper. The charge-transfer resistance at −0.15 V vs SCE, obtained from impedance data recorded in 0.1 M NaCl after 60 min, was measured as 21 kΩ cm² for copper indicating the build-up of corrosion products, while a lower resistance of 8 kΩ cm² was seen with the BV-modified copper. The estimated chloride content at the copper surface following immersion in chloride solutions was reduced from about 22% to 4% on modification with BV. Less protective properties were observed when the benzyl viologen was deposited from oxalate, sulfate and acetate solutions, and when the benzyl viologen was replaced with methyl or ethyl viologens, illustrating the importance of the supporting anions and viologen compound. The reduction of the di-cationic BV²⁺ to the radical cation was observed at −0.57 V vs SCE, while the further reduction of the radical species was seen at −0.73 V vs SCE, indicating that the deposited benzyl viologen exhibits its characteristic redox properties.

苄基紫精（BV）在氯化物阴离子的存在下沉积在铜上，以在铜上生成苄基紫精-氯化物层，其中紫精作为指示剂存在，并通过带负电荷的氯离子稳定。该层为下面的铜基板提供了良好的保护性能。将BV修饰的铜在0.1 M NaCl中极化后，在0.40 V vs. SCE的条件下，观察到较低的电流，通常为28μAcm ^-2，相比之下，未经修饰的铜的较高电流为1.75 mA cm ^-2。60分钟后从记录在0.1 M NaCl中的阻抗数据获得的-0.15 V vs SCE下的电荷转移电阻测量为21kΩcm ²铜表明腐蚀产物的积累，而BV改性铜的电阻较低，为8kΩcm ²。在用BV改性后，浸入氯化物溶液后铜表面的估计氯化物含量从约22％降低到4％。当从草酸盐，硫酸盐和乙酸盐溶液中沉淀出苄基紫精，并用甲基或乙基紫精代替苄基紫精时，观察到的保护性较差，这说明了支持阴离子和紫精化合物的重要性。双阳离子BV ²⁺的还原 相对于SCE，在-0.57 V处观察到自由基阳离子的氧化还原，而相对于SCE，在-0.73 V处观察到自由基物种的进一步还原，表明沉积的苄基紫精表现出其特征性的氧化还原特性。