Ultrasound assist synthesis of rod-like MnO2/ thermal reduced GO/annealed PANI ternary composite and used as a cathode for asymmetrical 2032-coin cell supercapacitors

The integration of heterojunction structures in ternary composite materials is an effective approach for enhancing their characteristics in numerous applications. In this study, we present the successful amalgamation of two materials with high electron conductivity, namely reduced graphene oxide (rGO) and carbon nanoparticles derived from polyaniline, with high capacitance materials consisting of a-MnO2 rods. Structural and morphological studies reveal that the MnO2/T.rGO/A.PANI hybrids are composed of carbon nanoparticles from the PANI induced into the interconnected network of rGO sheets and MnO2 rods. The ternary composite material MnO2/T.rGO/A.PANI has a high specific capacitance of 1140 F/g at 1 A/g, which is significantly greater than a-MnO2 (391.2 F/g). Due to its low resistance and better electrochemical performance, it can be used for the fabrication of asymmetric supercapacitors. MnO2/T.rGO/A.PANI as the positive electrode and reduced graphene oxide (rGO) as the negative electrode can be used in this asymmetric supercapacitor (ASC) construction. The asymmetric coin cell (ACC) is comprised of MnO2/T.rGO/A.PANI//H.rGO demonstrates notable electrochemical performance characteristics. In particular, its specific capacitance is rather high at 180.6 F/g at a current density of 1 A/g, its rate capability is 64 Wh/kg at a power density of 800 W/kg, and its cycling stability is quite good, maintaining 97 % of the starting value after 5000 cycles. Low leakage current and high self-discharge are hallmarks of ACC devices. These results imply the energy storage device can power blue LEDs for 20 min. The findings indicate that the MnO2/T.rGO/A.PANI//H.rGO ACC will soon play a major role in the energy environment. [Display omitted] •MnO2/T.rGO/A.PANI nanocomposites were prepared by sonication method.•The introduction of A.PANI enhances the electronic conductivity of the nanocomposite.•The MnO2/T.rGO/A.PANI nanocomposites exhibit excellent capacitive performance and indication of good cycle stability.