| Preparation and electrochemical characterization of Ni-Co oxides/CNT composites for supercapacitor application |
| Paper ID : 1080-UFGNSM-FULL |
| Authors: |
|
morteza Saghafi Yazdi * Department of Materials Science and Engineering, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran |
| Abstract: |
| In this paper Ni-Co oxide/carbon nanotubes (with equal Co+2/Ni+2 mole ratio) composite material for supercapacitor application were prepared by chemically depositing of Ni-Co hydroxide onto CNTs pretreated by ultrasonication and followed by thermal annealing at 300 °C. Scanning electron microscopy (SEM) have been exploited to characterize the morphology of composite materials and electrochemical properties of electrodes were studied by cyclic voltammetry technique. The SEM images show that the nucleation of the Ni-Co hydroxide formed on the outer walls of CNTs due to ultrasonic cavitations, and then Ni-Co oxide coated uniformly on the surface of the individual CNTs after thermal annealing. The cyclic voltammetry curve of the CNT electrode has a nearly rectangular shape and there is no peak during the charging and discharging process, which indicates the absence of significant oxidation-reduction reactions and shows only typical double-layer capacitive behavior. All composite electrodes have oxidation-reduction peaks which correspond to the redox Faradaic reactions on the electrode–electrolyte interface with elevated specific capacitance. The specific capacitance of Co-Ni oxide/CNT was measured to be 300 F/g, which is higher than measured capacitance of other electrodes in 1 M NaOH electrolyte. The good electrochemical characteristics of composites can be attributed to the three-dimensionally interconnected nanotubular structure, porous network structure, good electrical conduction pathways, high access for the electrolyte solution, and consequently increased composite/solution interfacial contact area. |
| Keywords: |
| Carbon nanotube; Co-Ni oxide; Energy storage; Supercapacitor |
| Status : Paper Accepted (Poster Presentation) |
