Synthesis of La and Ce Mixed MnO2 Nanostructure/rGO Composite for Supercapacitor Applications

Abstract This paper reports the synthesis of MnO 2 nanorods by a facile hydrothermal method for supercapacitor applications. Lanthanum and cerium at different weight ratios were mixed to alter the morphology of the MnO 2 nanomaterials. The crystalline nature and morphology of the synthesized MnO 2 nanocomposites were examined by powder XRD and field emission scanning electron microscopy, respectively. Cyclic voltammetry, charge−discharge measurements, and electrochemical impedance spectroscopy were used to examine the electrochemical performance of La and Ce‐mixed MnO 2 nanocomposite. The 1La3Ce−MnO 2 nanocomposite electrode exhibited a high specific capacitance of 575.25 F g −1 at a current density of 1 A g −1 . Carbon nanotubes, reduced graphene oxide, and activated carbon materials were mixed with the 1La3Ce−MnO 2 nanocomposite to improve the electrochemical performance. Among the three different electrodes, the rGO‐mixed 1La3Ce−MnO 2 nanocomposite electrode exhibited a relatively high specific capacitance of 951.25 F g −1 with a high energy density of 84.56 Wh kg −1 at a current density of 1 A g −1 . A rGO@1La3Ce−MnO 2 /rGO@1La3Ce−MnO 2 symmetric supercapacitor device was also fabricated and its electrochemical behavior was studied. The analyses showed that the rGO‐mixed 1La3Ce−MnO 2 nanocomposite is a suitable material for supercapacitor electrode fabrication.