The reversible anomalous high lithium capacity of MnO2 nanowires

Abstract

MnO₂ as a material for supercapacitors is generally predicted to insert only one cation per unit cell. However, it is shown here to reversibly insert more than one cation in an organic electrolyte; however, in an aqueous electrolyte, the insertion ion is actually shown to be a combination of protons and cations.