Procedure for pH monitoring in porous materials

The final outcome of the developed work has been a new electrochemical sensor with high durability and reliability, applicable for use in porous materials such as concrete and mortar, and the optimization of a method capable of monitoring the pH in these media when the sensor is embedded within them. These sensors apply a potentiodynamic excitation signal in the range of potentials where the reaction of interest occurs. From the processing and analysis of the electrical current obtained as a response, the pH of the pore solution in the material where the sensor is embedded is estimated. The voltammetric pH sensor can be prepared using metals whose peak potentials, related to the adsorption/desorption of OH⁻ and O₂, shift to more positive values as the pH decreases.