Investigation into the Anodic Dissolution Processes of Copper in Neutral and Acidic Sulfate Solutions with the In-line Digital Holography

Abstract

The films formed on the surface of copper during its anodic dissolution in the neutral or acidic sulfate solution were studied with the in-line digital holography. The results showed that the mixture films were formed on the surface of copper in the neutral or acidic sulfate solution: the inner oxide film and the outer salt film. Although there are defects in the oxide film caused by the sulfate ions, the oxide film other than the salt film mainly inhibits the anodic dissolution at the high anodic potentials.

A study on synergistic effect of chloride and sulfate ions on copper corrosion by using electrochemical noise in asymmetric cells

“…Following the results of the previous section, EIS and polarization measurements are performed to evaluate the pitting corrosion behavior of copper metal in the presence of chloride and sulfate ions. Most theories associated with copper pitting regarded chloride as accounting for pitting attacks while excluding the direct contribute on of sulfate ions 38 , 45 , 46 . According to the previous section and the other research, in the presence of both sulfate and chloride ions, as an aggressive medium, the pit germination is mainly associated with the presence of both these species 45 , 46 .…”

“…Most theories associated with copper pitting regarded chloride as accounting for pitting attacks while excluding the direct contribute on of sulfate ions 38 , 45 , 46 . According to the previous section and the other research, in the presence of both sulfate and chloride ions, as an aggressive medium, the pit germination is mainly associated with the presence of both these species 45 , 46 . The normal EIS measurements conducted in 0.3 M NaCl + 0.3 M Na 2 SO 4 0.6 M NaCl and 0.6 M Na 2 SO 4 solutions at 60 °C can be observed in Fig.…”

“…Referring to Table 4 , the ohmic and charge transfer resistances in the solution of 0.3 M NaCl + 0.3 M Na 2 SO 4 were less than those obtained from solutions having either chloride or sulfate. Even though there are different opinions about the corrosion mechanism of copper in chloride solution, it is generally accepted that insoluble salt film CuCl is formed; however, this kind of salt film cannot be formed in the sulfate solution, as a result, the pitting corrosion is enhanced in the mixture solution of Cl − and SO 4 2− ions 45 , 46 .…”

Review of the application of digital holography in corrosion studies

“…The image processing method for reconstructing holograms has been used thus far and has played an important role in corrosion and electrochemical studies. DH reconstruction technology has been widely used, such as in situ observation of the transient concentration gradient in the diffusion layer (Yuan et al , 2008), local corrosion at the interface (Li et al , 2012), the diffusion layer during the rupture processes of the passive film of 800 alloy (Xia et al , 2015), anodic dissolution processes in neutral and acidic sulfate solutions (Hu et al , 2016), monitoring reactions at the interface of lithium-ion batteries (Lai et al , 2017) and the effect of magnetic fields on the IGC of nickel 690 in sodium chloride solution (Xu et al , 2022).…”

Surface Characterization Techniques: A Systematic Review of their Principles, Applications, and Perspectives in Corrosion Studies

“…More recent developments with multiscale characterization techniques that assess surface topography changes at the nanoscale have enabled the electrochemical determination of dissolution rates. Particularly, the atomic force microscopy (AFM) [18][19][20][21][22][23][24] and quantitative phase microscopy (QPM) techniques, including vertical scanning interferometry (VSI) [25][26][27][28] and digital holographic microscopy (DHM), [29][30][31][32][33][34][35][36][37][38] have evolved as major microto nanoscale topographic techniques to provide early-stage visualization and quantification of corrosion at the nanoscale. The powerful approach provides different types of information (e.g., characteristics of grains, phases, and surface layers) and insights into the region of interest to gain a comprehensive understanding of the corroding system.…”