Facile synthesis of reduced graphene oxide, titanium (IV) oxide, polythiophene, and carbon black nanocomposites and their supercapacitor applications

In this paper, a novel hybrid electrode materials together with graphene oxide or reduced graphene oxide (GO/rGO), titanium dioxide (TiO2), polythiophene (PTh), and carbon black (CB) were prepared an easy, low cost, and sustainable approach to synthesize GO/TiO2/PTh and rGO/TiO2/PTh/CB nanocomposites. In addition, GO/TiO2/PTh by different weight amount of TiO2 (0.05, 0.075, 0.1, and 0.125 g) were studied in two-electrode system for supercapacitor device applications. Nanocomposites were characterized by Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), scanning electron microscopy-energy-dispersive X-ray (SEM-EDX), atomic force microscopy (AFM) analysis, thermogravimetric-differential thermal analysis (TGA-DTA), Brunauer-Emmett-Teller (BET) analysis, and four-point probe analysis. The highest specific capacitance was achieved as C-sp = 1292.63 F/g for rGO/TiO2/PTh/CB nanocomposite at 2 mV/s by CV method. The highest electrical conductivity was observed as (sic) = 2.24 x 10(-3) S/cm for PTh. PTh increases the electron transfer movement together with TiO2 and CB nanoparticles. The surface area (58.62 m(2)/g for rGO) and pore volume of rGO (0.027 cm(3)/g for rGO) support the better electrochemical performance of rGO/TiO2/PTh/CB nanocomposite. Moreover, the long-term stability experiments show that the highest initial specific capacitance preservation was obtained as 110% for rGO/TiO2/PTh/CB nanocomposite at 100 mV/s for 1000 charge-discharge cycles. Moreover, it exhibits high coulombic efficiency. Electrochemical impedance spectroscopic (EIS) results were evaluated to interpret equivalent circuit models of [R-S(C-1(R-1(R2C2)))] obtained from ZSimpWin 3.22 simulation programme.