Direct growth of cobalt hydroxide rods on nickel foam and its application for energy storage

The present work reports synthesis of cobalt hydroxide (Co(OH)2) rods on nickel foam and its supercapacitor application. Hierarchical Co(OH)2 rods with length of approximately 3.5aμm and diameter of approximately 400anm were prepared by one-step, simple, and inexpensive chemical-bath-deposition method. The direct growth of Co(OH)2 rods on the Ni foam gave three dimensional (3D) structure for easy access of electrolyte throughout material surface. Also, well-adhered interface between Co(OH)2 rods and Ni-foam surface gave better conduction channels. Detailed electrochemical study was performed by using cyclic voltammetry and galvanostatic charge/discharge measurements. The results demonstrate that Co(OH)2 rods on Ni foam are efficient electrodes for supercapacitor application. Time for a bath! One-step, simple, and inexpensive synthesis of Co(OH)2 rods on Ni foam by the optimized chemical-bath-deposition method is described. The Ni-foam substrate can serve both as current collector and give nucleation sites for growth of Co(OH)2 rods, which eliminates the use of ancillary conducting material and binder (see figure). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.