Measuring Concentration Dynamics in Porous Media
Development of new tools to observe ionic concentration in porous media

Conventional optical microscopy cannot be used to directly image flow and concentration in a porous medium due to the light scattering differences between the liquid and solid scaffold. A Harvard MRSEC team led by Shmuel Rubinstein has developed a new method and device to measure the ionic concentration dynamics in a porous medium. By formulating an electrolyte solution and fluorescent dye that match the index of refraction of the porous material, the spatiotemporal patterns of concentration under an applied voltage have been directly observed. Unraveling the intriguing dynamics of ion transport at a microscopic level in a complex medium may provide the guidance to control ion transport for application in electrochemical systems.