ICP-AES and microRaman corrosion behaviour investigation on Pb, Sb, Bi tellurides in sodium chloride solution

• MicroRaman and ICP-AES investigation is a useful approach for the study of corrosion.
• A passivation film protects PbTe and Bi2Te3 bulk samples from a progressive corrosion.
• ICP-AES shows a high Sb release; the Pb and Bi releases can be considered negligible.
• PbTe and Bi2Te3 show very good corrosion behaviour in the chloride environment.

Tellurides are in years considered among the best intermetallic compounds for thermoelectric applications in the low-intermediate- temperature range.The corrosion behaviour of pure Pb, Sb and Bi tellurides is investigated in this work through a spectroscopic approach. The samples are synthesized using a muffle furnace and then placed in 0.1 M NaCl aerated solution at room temperature for 48 days. All samples are characterized, prior to and after immersion, in terms of crystal structure, morphology and phases composition (SEM-EDXS, XRD). A study of the ionic release, using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) analysis, is also carried out. Furthermore, a microRaman spectroscopy study is performed on surface corrosion products. The preliminary results reveal that PbTe and Bi2Te3 show the best corrosion resistances in the considered environment.