Durability of an As2S3 chalcogenide glass: Optical properties and dissolution kinetics

The durability of a As2S3 chalcogenide glass composition was studied in de-ionized water at different temperatures (60–90 °C) for different periods of time, up to 120 days. The evolutions of the chemical composition and the pH of the solutions as well as the optical transmission of bulk samples, in the 2–10 μm region, were measured as a function of corrosion time. Atomic force microscopy and optical microscopy were used to investigate the roughness of corroded surfaces and the evolution of surface defects. The water corrosion of As2S3 glass was found to follow a congruent dissolution mechanism, a possible glass–water reaction mechanism was proposed. The optical transmission of the glass was found to be affected by the corrosion. The optical loss increased from 4 to 21% with corrosion time, this variation was attributed to the texturation of the surface by the reaction of corrosion. Moreover, the experimental results show that high temperature value enhances the corrosion reaction: an activation energy of 103 ± 2 kJ/mol was computed from experimental measurements.