Controllable Synthesis of V2O5/Mn3O4 Nanoflakes and rGO Nanosheets: To Investigate the Performance of All Solid‐State Asymmetric Supercapacitor Device

Abstract Different nanostructured/composite materials are considered as a promising electrode material which enhances the electrochemical activity of the individual substances. V 2 O 5 /Mn 3 O 4 composite material is synthesized using hydrothermal method at different reaction time ranging from 12 h to 24 h. Obviously, by varying the reaction time, the morphology of composite changes from individual flakes to agglomerated flakes. The change in surface morphology of the material is observed from the SEM images. Electrochemical performance of V 2 O 5 , Mn 3 O 4 , V 2 O 5 /Mn 3 O 4 ‐1 , V 2 O 5 /Mn 3 O 4 ‐2 V 2 O 5 /Mn 3 O 4 ‐3 , V 2 O 5 /Mn 3 O 4 ‐4 and rGO is studied using cyclic voltammetric, charge/discharge, and electrochemical impedance spectroscopic studies. At a current density of 5 A g −1 , V 2 O 5 , Mn 3 O 4 , V 2 O 5 /Mn 3 O 4 ‐3 , and rGO nanosheet exhibit the maximum specific capacitance of 441, 190, 1008 and 464 F g −1 respectively. Moreover, the asymmetric supercapacitor device is constructed using V 2 O 5 /Mn 3 O 4 ‐3 and rGO nanomaterials. At 2 A g −1 , the asymmetric V 2 O 5 /Mn 3 O 4 ‐3 and rGO device obtains the highest energy density of 44.9 W h kg −1 and the corresponding power density is 1.76 kW kg −1 .