Characterisation of nickel hydroxide precipitated from solutions containing Ni2+ complexing agents

Abstract

Nickel hydroxide prepared by a complexation-precipitation route yields a very fine particle material. The physicochemical properties and electrochemical charge-discharge capacities are compared with electrochemically prepared nickel hydroxide. In the present study, an attempt is made to prepare nickel hydroxide using nickel nitrate and complexing agents such as sodium succinate (SS), ethylene-diamine-tetra acetic acid (EDTA), sodium potassium tartrate (SPT) and tri-ethanol amine (TEA), The DTA analysis of the nickel hydroxide revealed the presence of a broad endothermic peak at similar to120 degreesC and a sharp endothermic one at similar to435 degreesC. The order of water association in the lattice of nickel hydroxide produced follows the order TEA>EDTA>SS. The electrochemical property resulted in higher discharge capacity (208 mA h/g) for TEA as complexing agent and lowest (107 mA h/g) for SS. (C) 2003 Published by Elsevier Science B.V.