Microscale Corrosion Inhibition Behavior of Four Corrosion Inhibitors (BTA, MBI, MBT, and MBO) on Archeological Silver Artifacts Based on Scanning Electrochemical Cell Microscopy

The problem of corrosion-induced discoloration and embrittlement
in silverware is a significant concern for the long-term preservation
of excavated archeological silver artifacts, even after thermal restoration.
The key to addressing this issue lies in the meticulous selection
and evaluation of corrosion inhibitors that possess targeted corrosion
inhibition capabilities. This study focuses on the evaluation of corrosion
inhibitors for archeological silver artifacts using scanning electrochemical
cell microscopy (SECCM) and X-ray photoelectron spectroscopy (XPS).
The researchers aimed to compare the inhibition effects of four corrosion
inhibitors [1,2,3-benzotriazole (BTA), 2-mercaptobenzimidazole (MBI),
2-mercaptobenzothiazole (MBT), and 2-mercaptobenzoxazole (MBO)] on
a simulated Ag–Cu alloy sample and understand their mechanisms.
The results showed that MBT exhibited better corrosion inhibition
for microstructural regions with higher silver content due to its
ability to form stable chelation structures with Ag(I). MBO exhibited
better corrosion inhibition for microstructural regions with higher
copper content due to its strong affinity with Cu(I). The targeted
corrosion inhibition ability for the β-phase was ranked as MBO
> BTA ≈ MBI > MBT, while for the α-phase the ranking
was MBT > MBO > MBI > BTA. The study demonstrated the feasibility
and capabilities of SECCM in the targeted screening of corrosion inhibitors
for different compositions and microstructural regions in archeological
metal artifacts. This study highlights the potential of SECCM in corrosion
inhibitor research for archeological metal artifacts and wider applications
in metal material corrosion protection.