Research Article Influence of Concentration and Electrodeposition Time on the Electrochemical Supercapacitor Performance of Poly(3,4-Ethylenedioxythiophene)/Graphene Oxide Hybrid Material Nur Hawa Nabilah Azman, 1 Hong Ngee Lim, 1,2 and Yusran Sulaiman 1,2 1 Department of Chemistry, Faculty of Science, Universiti Putra Malaysia (UPM), 43400 Serdang, Selangor, Malaysia 2 Functional Device Laboratory, Institute of Advanced Technology, Universiti Putra Malaysia (UPM), 43400 Serdang, Selangor, Malaysia Correspondence should be addressed to Yusran Sulaiman; yusran@upm.edu.my Received 14 August 2016; Revised 27 October 2016; Accepted 8 November 2016 Academic Editor: Stefano Bellucci Copyright © 2016 Nur Hawa Nabilah Azman et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Poly(3,4-ethylenedioxythiophene)/graphene oxide (PEDOT/GO) composites with wrinkled paper-like sheets morphology were electropolymerized potentiostatically at 1.2 V with diferent electrodeposition times (1–30 min) and various concentrations of GO (0.5, 1.0, 1.5, and 2.0 mg/mL). Te electrochemical properties of PEDOT/GO composites as an electrode material for supercapacitor were investigated using cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge (GCD). Te CV results revealed that PEDOT/GO containing 1.0 mg/mL GO and electropolymerized for 10 minutes exhibited the highest specifc capacitance (157.17F/g). Tis optimum PEDOT/GO was found to have energy and power density of 18.24 W/kg and 496.64 Wh/kg, respectively, at 1.0 A/g current density. Te resistance of charge transfer obtained for PEDOT/GO is very low (13.10 Ω) compared to PEDOT (638.98 Ω), proving that PEDOT/GO has a good supercapacitive performance due to the synergistic efect of the high conductivity of PEDOT and large surface area of GO. 1. Introduction In recent years, there has been a greater demand for energy storage devices due to the defciency of energy source. Tere- fore, the development of energy storage device such as super- capacitor is expanding rapidly. Supercapacitor also known as ultracapacitor is an electrical energy storing device which bridges the gap between batteries and capacitors [1, 2]. Super- capacitor possesses fast charge-discharge cycle, high power density, and longer life span and is also environmentally friendly compared to battery [3]. Supercapacitor has a poten- tial to deliver greater acceleration (through rapid discharge capability) and enhance the regenerative braking systems (through fast charge capability) for hybrid and pure electric vehicles [4]. However, the energy density of batteries is greater in comparison to supercapacitors [5]. Supercapacitors can be classifed into two main categories based on its charge storage mechanism, that is, electric dou- ble-layer capacitor (EDLC) and pseudocapacitor. EDLC stores charge non-Faradaically or electrostatically in double layers where there is no electron transfer occurring at the interface of the electrode [6, 7]. Graphene, activated carbon, and carbon nanotubes (CNT) with high porosity and surface area are types of carbon-based materials used for EDLC [8]. Pseudocapacitor which is made up of pseudocapacitive mate- rials, that is, metal oxides and conducting polymers (CPs), stores charges Faradaically or through redox reactions which occur at the electrolyte/electrode interface that contribute the capacitance [9, 10]. EDLC compared to pseudocapacitor is able to deliver higher power density and longer life cycle due to the high porosity, mechanical strength, and surface area provided by Hindawi Publishing Corporation Journal of Nanomaterials Volume 2016, Article ID 5935402, 10 pages http://dx.doi.org/10.1155/2016/5935402