Adsorption of ions from aqueous solutions into pores, as narrow as 3.7Å was observed, using linear sweep cyclic voltametry. The conductivity of the solution in pores of less than 7Å diameter is several orders of magnitude lower than that of a free
0.1N normalNaCl
solution in contact with the carbon electrode. It seems negligibly slow in pores of less than 3.7Å diameter, which are still completely filled with water. Highly oxidized ultramicroporous carbons show much lower double layer capacitance at positive potentials than nonporous carbon surfaces. This is interpreted as repulsive ion‐dipole interaction of the anion with the dipole of the chemisorbed oxygen. Ions can penetrate the tiny pores after depletion of the hydration sheath. The double layer charging rate is therefore much slower if
0.1N normalNaCl
is replaced by
0.1N normalLiCl
. A brief discussion is presented in order to confirm that the electroactive surface groups can be treated in terms of (capacitative) double layer charging.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.