One-step fabrication of electrochemically reduced graphene oxideickel oxide composite for binder-free supercapacitors

摘要

A three-dimensional (3D) graphene/Nickel oxide (ERGO/NiO) composite electrode have been fabricated directly on a Nickel foam substrate via a one-step electrochemical co-deposition in an aqueous solution containing Nickel nitrate and GO. By using this simple and one-step electrochemical deposition, it is possible to produce binder-free composite electrodes with improved electrochemical properties using a low-cost, facile and scalable technique. It is observed from FE-SEM images that graphene oxide sheets affect the electrodeposition of nickel oxide. The optimized ErGO/NiO electrode developed in this work exhibits high charge storage capacity with a specific capacitance of 1715.5 F g(-1) at current density 2 A g(-1) and hierarchical morphological structure which facilitates electrolyte diffusion to the electrode surface. A good cycling stability was observed for the modified electrodes in alkaline media. EIS measurements showed low values of internal resistance (R-s) and charge transfer resistance (R-ct) for the modified electrodes, indicating that the prepared nanocomposite is appropriate for supercapacitor applications in comparison to NiO/NF electrode. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.