Electrical double layer in nano-pores of carbon electrodes: Beyond CDI; sensing and maximizing energy extraction from salinity gradients

The important phenomenon of electrical double layer (EDL) is often described by mathematical relations between surface charges, variation of electrostatic potentials with distance and distribution of ions across the interface between charged surfaces (or particles) and electrolyte solutions. A major advance was made in the last decade in understanding complex EDL relationships with an emphasis on nano-porous carbonaceous materials. These understandings were usually exploited for the interpretation of electro-sorption phenomena connected to capacitive deionization (CDI) processes. The aim of this short paper is to demonstrate, based on previous studies, how models of EDL in nano-porous carbons can be the basis for modification of carbonaceous materials for other applications, like sensors and energy extraction from salinity gradients.