Abstract: The present invention describes supercapacitors with enhanced energy density and power density, achieved largely through use of electrodes that incorporate ternary oxide(s). Ternary oxide(s) are ternary nanostructures have the formula AxByOz, wherein x ranges from 0.25 to 24, and y ranges from 0.5 to 40, and z ranges from 2 to 100, and wherein A and B are independently selected from groups of elements specified in this application.