Polyaniline/manganese nickel oxide/graphene composites as electrode materials for supercapacitors

Abstract This study introduces a novel electrode material featuring a core‐shell intercalation structure. The material was synthesized using a simple and scalable method suitable for industrial replication. The outer layer of the electrode material comprises polyaniline, enveloping a nuclear structure composed of manganese dioxide and nickel oxide. This core‐shell configuration is then integrated into the lamellar structure of graphene oxide, resulting in the formation of PANI@(MnO 2 + NiO)@GO composite. The combination of polyaniline, metal oxides, and graphene oxide demonstrates robust adsorption capacity, leading to the development of a three‐dimensional stable structure between the core and the shell. Additionally, graphene oxide contributes to the bilayer capacitance of the composites, resulting in simultaneous multiple synergistic effects and improved charge storage capacity. Electrochemical characterization reveals exceptional properties of this composite material, exhibiting a specific capacitance of 396 F g −1 at a current density of 0.5 A g −1 in a three‐electrode configuration. Furthermore, the material retains 82.6% of its capacitance after undergoing 3000 consecutive charge/discharge cycles. Calculations estimate the energy density and power density of this composite in a supercapacitor employing 1 M Na 2 SO 4 electrolyte to be 43.2 W h kg −1 and 249.99 W kg −1 , respectively.