Corrosion on silvered-glass solar reflectors exposed to accelerated aging tests with polluting gases: A microscopic study

• Published in: Corrosion science Vol. 176; p. 108928
• Main Authors: García-Segura, A., Fernández-García, A., Ariza, M.J., Sutter, F., Watermeyer, P., Schmücker, M., Valenzuela, L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01-11-2020; Elsevier BV
• Subjects: Accelerated aging test; Accelerated aging tests; Atmospheric corrosion tests; Copper; Corrosion; Corrosion of copper and silver thin films; Corrosion products; EDS; FIB; Glass plates; H2S; Hydrogen sulfide; Industrial atmospheres; Nitrogen dioxide; NOx; Pollutants; Polluting gases; SEM; Silvered-glass solar reflectors; SO2; Solar reflectors; Sulfur dioxide; Thin films; Accelerated aging test; Silvered-glass solar reflectors; Polluting gases; Corrosion of copper and silver thin films; EDS; NOx; SO2; H2S; SEM; FIB
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2020.108928

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•SEM, EDS and FIB are employed to study corrosion in Ag-glass solar reflectors.•Polluting gases (SO2, H2S and NOx) have a great influence on reflector degradation.•For all gas atmospheres, the Cu-layer is the critical component. It is corroded first and protects silver.•Corrosion products and mechanisms depend on gas type, humidity and temperature•Heavy metals of the rear protective paints (Zn, Fe) also play a significant role.
Silvered-glass solar reflectors consist of a reflective layer (RL), composed of silver and copper thin-films, back-protected by paint layers on a glass plate. The RL is prone to corrosion, especially in industrial atmospheres with polluting gases. After applying accelerated aging tests with gaseous pollutants (SO2, H2S, NO2), SG-R samples are studied by SEM and EDS, including FIB preparation. As expected the copper thin-film is firstly corroded, followed by the silver corrosion. Deposits of different corrosion products were found on the reflector’s surface, depending on the polluting gas used. The rear protective paint layers also play an active role.