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In this work, a new electrode active materials including reduced graphene oxide (rGO), Manganese dioxide (MnO2) / polyterthiophene (PTTh) has been synthesized as a nanocomposite using in-situ polymerization method, microwave-assisted method for obtaining reduced graphene oxide and chemical synthesis of metal-oxide for supercapacitor devices. A ternary nanocomposites of rGO/MnO2/PTTh were characterized by the analysis of Fourier transform infrared-attenuated transmission reflectance (FTIR-ATR), Raman spectroscopy, scanning electron microscopy-energy dispersion X-ray analysis (SEM-EDX), transmission electron microscopy (TEM), thermal-gravimetric analysis (TGA-DTA), Brunauer-Emmett Teller (BET) pore analysis, Ultraviolet-visible (UV-vis) spectrophotometer, X-ray diffraction (XRD) analysis, electrochemical impedance spectroscopy (EIS), galvanostatic charge/discharge (GCD), and cyclic voltammetry (CV). The highest specific capacitance (Csp) was obtained as Csp = 908.86 F/g for rGO/MnO2/PTTh nanocomposite at 1 mV/s for [MnO2]o/[TTh]o = 1/3. Moreover, equivalent electrical circuit model of LR(QR) was chosen to interpret EIS analysis of supercapacitor device. rGO/MnO2/PTTh nanocomposite has both electrochemical double-layer capacitance and pseudocapacitance due to the fast and reversible redox processes related to the π-conjugated polymer chains. [ABSTRACT FROM AUTHOR]

A new nanocomposite electrode incorporating poly(3,4-ethylenedioxythiophene) (PEDOT) within the nanocomposite film of the reduced graphene oxide / Titanium dioxide (TiO2) was synthesized to be used in supercapacitor devices. We used constant EDOT monomer for in-situ polymerization and different initial monomer concentration ratio of [rGO]o/[TiO2]o = 1/1, ½ and 1/5. The obtained nanocomposites were examined by FTIR-ATR, UV-vis, SEM-EDX, TGA-DTA, BET surface areas and pore distribution, XRD, TEM, AFM, CV, GCD and EIS analyses. The results showed that graphene oxide was successfully reduced to rGO by means of the microwave-assisted method. It was confirmed by the increases in the specific capacitance of (Csp = 652 F/g) at 1 mV/s for the rGO/TiO2/PEDOT nanocomposite at [rGO]o/[TiO2]o = 1/5. This was related to the pore size (~33.50 nm) of the material for rGO/TiO2/PEDOT at [rGO]o/[TiO2]o = 1/5 obtained from BET analysis. The other Csp values were 475.33 F/g for [rGO]o/[TiO2]o = 1/2, 114.09 F/g for rGO/PEDOT and 48.02 F/g for [rGO]o/[TiO2]o = 1/1. Equivalent circuit model of Rct(CdlRct) was analyzed via ZSimpWin and TINA programmes. A facile and inexpensive approach for a ternary nanocomposite synthesis of rGO/TiO2/PEDOT was presented for future supercapacitor applications.ᅟ [ABSTRACT FROM AUTHOR]