Electrochemical performance of binder-free Ni(OH)2/RGO battery type electrode materials for supercapacitor

Abstract

ABSTRACT Ni(OH)2/reduced graphene oxide (RGO) core-shell hybrid nanostructure has been synthesized employing a facile and inexpensive chemical-precipitation technique. The synthesized core-shell nanostructures, comprising Ni(OH)2 at the core and RGO as shell, were then coated on commercially available Ni foam used as an electrode. Prepared Ni(OH)2/RGO nanospheres were analyzed by Raman analysis for structural information. In the Raman spectrum, the peaks at 1323 and 1612 cm−1 correspond to the D and G bands of RGO, respectively. The peaks at 468 and 335 cm−1 depict the characteristic bands of Ni(OH)2 . The core-shell morphology of the hybrid was established from Transmission Electron Microscope (TEM) images. The lattice fringes are measured to be 0.33 nm for RGO layers and 0.22 nm for Ni(OH)2 core, which correspond to (002) plane of RGO and (101) plane of Ni(OH)2. For electrochemical studies, the as-prepared Ni(OH)2/RGO hybrid was used as a battery-type electrode in supercapacitor. The results indicate that the Ni(OH)2/RGO core-shell hybrid nanostructure exhibits a maximum specific capacity of 513.8 Cg−1 at 10 mV/s with a maximum energy density of 119.4 Whkg−1 at 1250 Wkg−1 power density.