Corrosion of chalcogenide glasses in basic aqueous solutions

CONDE GARRIDO, J. M.; SILVEYRA, J. M.; RODRIGUEZ CUELLAR, O.; MARIA ANDREA UREÑA

Montpellier

Conferencia; ECASIA 2017, European Conference on Applications of Surface and Interface Analysis; 2017

Chalcogenide glasses are amorphous materials used in great variety of applications: infraredoptics, chemical sensors, gas sensors, phase change memories, solid-state electrolytes, etc.In previous works, our group has discovered that Agx(Ge0,25Se0,75)1−x (at. %) bulkglasses are heterogeneous and consist of two phases: a Ag-rich phase and a Ag-poor phase.In the range of compositions 0.08 < x < 0.1, the glasses suffer a spinodal decompositionupon solidification. Outside this range, a binodal decomposition takes place.A high resistance to acidic media characterizes these materials but they are corroded bybasic solutions. Our group has shown in previous works that the Ag-poor phase is moreeasily corroded than the Ag-rich phase.In this work, we studied bulk AgGeSe glasses with x = 0 and 10 by immersing them in KOH(0.3M) solutions at various temperatures. We observed the samples by SEM, measured themass loss as a function of time, and estimated the reaction order and the activation energy.