الفهرس 
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Abstract
Supercapacitors (SCs) are one of the foremost distinguished and proficient energy storage devices, for the following reasons: they can store higher energy than dielectric capacitors and also, higher power than Li-ion batteries, low fabrication costs, longer cyclic stability, high rate charge and discharge, safety and simple operational mechanism. Based on its distinguished properties, they have wide range of applications in the energy storage field like distributed sensor networks, hybrid electric vehicles and mobile electronic devices and etc. The active constituent materials and charge storage can classify SCs into two sorts: (i) The electrical double-layer capacitors (EDLCs), which are based on carbon materials characterized by high surface area. Their capacitance emerges as the result of charge accumulation at the interface between electrolyte-electrode. This process restricts the energy storable to the available electrode surface area, but it yields SC device with good cycling stability. (ii) The redox SCs or pseudo-capacitors (PCs), which are based on conducting polymers (CPs) or transition metal oxides. They store charge faradaically via redox reactions throughout the bulk material. They can storage dramatically large amounts of energy than EDLCs. Although PCs have higher charge storage capacity compared to EDLCs, they suffer from high cost and poor cyclic stability. To achieve the commercialization of SCs, devices need to appear a combination of long-term stability, high charge storage capacities, in addition to being cost-effectiveness. There are several ways to solve the problems of the SCs such as development of new architectures and nanostructures of the active material that have exhibited improve stability, facilitate ion diffusion, and increase the surface area. As well as manufacturing of new composites from faradaic materials and non-faradaic (carbon) in order to achieve a balance between the stability and the stored energy. Also the performance of supercapacitor could be improved by using nanostructured redox active materials. The main objective from this work is to synthesize and characterize the nanofibers of conducting polymers utilizing electrospinning technique and use them for energy storage applications. Among different CPs for PCs, Polyindole (PIND) is one of the proficient polymer material used in the application of SCs. Since it has distinguished properties including: good thermal stability, potential for blend formation with commercial polymers, it has features of both self-possessed polypyrrole (PPY) and poly (para-phenylene) such as high redox activity and also slow degradation rate properties. Based on these distinguished properties, it is one of the candidate’s polymer for acting as enhanced electrode material in the application of SCs. In this study, PIND was synthesized by chemical oxidative polymerization. Lab made electrospinning method has been successfully utilized to fabricate nanofibers from a blend of PIND and ultrahigh molecular weight polyacrylonitrile (PAN) to provide sufficient chain entanglements. A tiny amount of Graphene Oxide (GO) was introduced to the solution of PIND/PAN before the electrospinning to yield PIND/PAN/GO nanofibers for further improve the stability and capacity of the electrodes. The chemical structure and surface morphological of synthesized materials (PIND/PAN and PIND/PAN/GO) and the chemically prepared PIND powder were characterized utilizing scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The electrochemical performances and the possible application of the prepared PIND/PAN and PIND/PAN/GO nanofibers for utilizing as active materials for electrode in supercapacitor application were evaluated via cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) measurements. It was noted that the PIND/PAN/GO nanofibers webs exhibited a specific capacitance (4960 mF g-1) that higher than the capacitance of PIND/PAN nanofibers webs (1810 mF g-1) in 1 M H2SO4 at the same scanning rate of 5 mV/sec in the study of CV. The results illustrate the role of GO in improving the charge storage in the PIND electrode. Finally, our results suggesting that the synthesized nanofibers could be used for energy storage applications.