Print Email Facebook Twitter Potentiometric Response of Ag/AgCl Chloride Sensors in Model Alkaline Medium Title Potentiometric Response of Ag/AgCl Chloride Sensors in Model Alkaline Medium Author Pargar, F. (TU Delft Materials and Environment) Kolev, H (Bulgarian Academy of Sciences) Koleva, D.A. (TU Delft Materials and Environment) van Breugel, K. (TU Delft Materials and Environment) Date 2018-05-28 Abstract The stability and reproducibility of an Ag/AgCl sensors’ response in an alkaline medium are important for the application of these sensors in cementitious materials. The sensors’ response, or their open circuit potential (OCP), reflects a dynamic equilibrium at the sensor/environment interface. The OCP response in an alkaline medium is affected by the presence of hydroxide ions. The interference of hydroxide ions leads to inaccuracies or a delay in the sensors’ response to a certain chloride content. In this article, the potentiometric response (or OCP evolution) of the chloride sensors is measured in model solutions, resembling the concrete pore water. The scatter of the sensors’ OCP is discussed with respect to the interference of hydroxide ions at varying chloride concentration in the medium. The deviation of the sensor’s response from its ideal performance (determined by the Nernst law) is attributed to dechlorination of the AgCl layer and the formation of Ag2O on the sensor’s surface. Results from the surface XPS analysis of the AgCl layer before and after treatment in alkaline medium confirm these observations in view of chemical transformation of AgCl to Ag2O. To reference this document use: http://resolver.tudelft.nl/uuid:eae1238f-8e5d-41b8-9b15-166023ecf060 DOI https://doi.org/10.1155/2018/8135492 ISSN 1687-8434 Source Advances in Materials Science and Engineering, 2018 Part of collection Institutional Repository Document type journal article Rights © 2018 F. Pargar, H Kolev, D.A. Koleva, K. van Breugel Files PDF 8135492.pdf 2.41 MB Close viewer /islandora/object/uuid:eae1238f-8e5d-41b8-9b15-166023ecf060/datastream/OBJ/view