Table of Contents
Indian Journal of Materials Science
Volume 2015 (2015), Article ID 820193, 7 pages
http://dx.doi.org/10.1155/2015/820193
Research Article

Effect of Crystallinity of β- and βbc-Nickel Hydroxide Samples on Chemical Cycling

Department of Studies and Research in Chemistry, Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India

Received 28 May 2015; Accepted 12 July 2015

Academic Editor: Ramki Kalyanaraman

Copyright © 2015 Ramesh Thimmasandra Narayan. This 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.

Abstract

β-phases of nickel hydroxide and cobalt hydroxide samples crystallize in cadmium iodide type structure. β-cobalt hydroxide on oxidation generates β-CoOOH which crystallized in 3R1 polytype while the structure of β-phase of NiOOH polytype is less well understood. β- and -phases of nickel hydroxide samples were prepared by using ammonium hydroxide and sodium hydroxide as precipitating agents. Powder X-ray diffraction data shows that β-phase of nickel hydroxide is perfectly crystalline in nature while -phase of nickel hydroxide is poorly ordered. β- and -phases of nickel hydroxide samples were subjected to chemical oxidation using sodium hypochlorite. The oxidized phases of β- and -phases of nickel oxyhydroxide are highly disordered and the broadening of reflections in the powder X-ray diffraction patterns is due to the presence of structural disorder, variations in the crystallite size, and strain. On reduction of β- and -phases of nickel oxyhydroxide, the powder X-ray diffraction patterns visually match the powder X-ray diffraction data of the pristine phases of β- and -phases of nickel hydroxide indicating that the β-phase of nickel hydroxide does not transform to -phase of nickel hydroxide, but the particle sizes are significantly affected.