A major limitation of transition metal oxide-based electrodes for supercapacitors is their low
energy densities. Since the energy density is proportional to the specific capacitance and
square of the operating voltage, extending the voltage window of the electrode as well as
enhancing contacts with electrolyte is of utmost importance. In this paper, we focus on the
hybrid electrode based on Fe 2 O 3 and MnO 2 nanoparticles (NPs) which have different
redox potential ranges, aiming for the increase of the specific capacitance and operating …