Alkali metal iodide/carbon interface as a source of pseudocapacitance

The pseudocapacitive effects originating from the alkali metal iodide/carbon interface have been studied in aqueous medium. Five different solutions, i.e., lithium, sodium, potassium, rubidium and caesium iodides (1 mol L-1) have been tested as electrolyte in supercapacitors. The capacitance of positive electrodes operating in these solutions reached values higher than 1000 F g(-1), depending strongly on the alkali metal ion. (C) 2010 Elsevier B.V. All rights reserved.