Electronic properties of bulk and nanosheet forms of K1.33Mn8O16 have been studied. The K1.33Mn8O16 nanosheet is a semiconductor while the bulk is a metal. K1.33Mn8O16 Nanosheet is a more efficient electrocatalyst than bulk K1.33Mn8O16. High figure of merit of K1.33Mn8O16 nanosheet makes it an efficient cathode.