Corrosion mechanisms of silver thin films

Un article de Surface du verre et interfaces.

Ning Li (PhD 2008-2011) - Sergey Grachev - Elin Sondergard

 

 

EC-STM image of Ag film in NaOH

Silver thin films are widely used in silver based low-emissivity coatings, because of thermal insulation for buildings. These coatings are prone to corrosion during transport and storage before encapsulation in double glazing units. The corrosion phenomena could be due to pinholes and/or adhesion and stress issues within the thin film stack. It is necessary to identify these corrosion mechanisms in order to improve the durability of the coatings.

Four aspects of corrosion are investigated:

• Electrochemical reactions between silver layer and the solutions which contain the corrosives ions(sulphide and chloride ions),

• Corrosion kinetics by using the electrochemical quartz crystal microbalance (EQCM),

• Structural evolution by electrochemical scanning tunneling microscopy (EC-STM),

• XPS and ToF-SIMS analyses for identifying the corrosion products.

Collaborations

• Philippe Marcus, Anouk Galtayries - Laboratoire des Physicochimie des Surfaces- UMR 7045 - Chimie ParisTech, Paris, France