Communication—Demonstrating the Role of Mass Transport in Double Layer Formation

Herein we present insight into the structure and behaviour of the electrified interface between a planar non-porous glassy carbon electrode and an aqueous solution of 0.5 M Na 2 SO 4 . Specifically, a glassy carbon rotating disk electrode was used to show correspondence between increasing rotation rates, decreasing boundary layer thicknesses, and decreasing interfacial capacitance. The implication is that electrolyte counter charge is being dissipated by convective flow outside of the macroscopically thick boundary layer, indicating that electrolyte counter-charge extends substantially into the electrolyte.